Use IHtmlGenerator / TagBuilder in necessary tag helpers

Notes:
- Would be nice to completely remove the use of `AbpTagHelperService.RenderHtml`

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/AbpTagHelperService.cs

@@ -53,7 +53,7 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers
             return Task.CompletedTask;
         }
 
-        protected string RenderHtml(IHtmlContent content)
+        protected virtual string RenderHtml(IHtmlContent content)
         {
             using (var writer = new StringWriter())
             {

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Breadcrumb/AbpBreadcrumbTagHelperService.cs

@@ -1,8 +1,8 @@
-using System.Collections.Generic;
+using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Razor.TagHelpers;
+using System.Collections.Generic;
 using System.Linq;
-using System.Text;
 using System.Threading.Tasks;
-using Microsoft.AspNetCore.Razor.TagHelpers;
 
 namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Breadcrumb
 {
@@ -10,37 +10,31 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Breadcrumb
     {
         public override async Task ProcessAsync(TagHelperContext context, TagHelperOutput output)
         {
+            output.TagName = "nav";
+            output.Attributes.Add("aria-label", "breadcrumb");
+
             var list = InitilizeFormGroupContentsContext(context, output);
 
             await output.GetChildContentAsync();
 
-            SetInnerOlTag(context, output);
-            SetInnerList(context, output, list);
-
-            output.TagName = "nav";
-            output.Attributes.Add("aria-label", "breadcrumb");
-        }
-
-        protected virtual void SetInnerOlTag(TagHelperContext context, TagHelperOutput output)
-        {
-            output.PreContent.SetHtmlContent("<ol class=\"breadcrumb\">");
-            output.PostContent.SetHtmlContent("</ol>");
+            ProcessItems(context, output, list);
         }
 
-        protected virtual void SetInnerList(TagHelperContext context, TagHelperOutput output, List<BreadcrumbItem> list)
+        protected virtual void ProcessItems(TagHelperContext context, TagHelperOutput output, List<BreadcrumbItem> list)
         {
             SetLastOneActiveIfThereIsNotAny(context, output, list);
 
-            var html = new StringBuilder("");
+            var listElement = new TagBuilder("ol");
+            listElement.AddCssClass("breadcrumb");
 
             foreach (var breadcrumbItem in list)
             {
                 var htmlPart = SetActiveClassIfActiveAndGetHtml(breadcrumbItem);
 
-                html.AppendLine(htmlPart);
+                listElement.InnerHtml.AppendHtml(htmlPart);
             }
 
-            output.Content.SetHtmlContent(html.ToString());
+            output.Content.SetHtmlContent(listElement);
         }
 
         protected virtual List<BreadcrumbItem> InitilizeFormGroupContentsContext(TagHelperContext context, TagHelperOutput output)

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Carousel/AbpCarouselTagHelperService.cs

@@ -5,7 +5,6 @@ using Microsoft.Extensions.Localization;
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using System.Text;
 using System.Threading.Tasks;
 using Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.Microsoft.AspNetCore.Razor.TagHelpers;
 
@@ -32,6 +31,8 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Carousel
             await output.GetChildContentAsync();
 
             SetOneItemAsActive(context, output, itemList);
+
+
             SetItems(context, output, itemList);
             SetControls(context, output, itemList);
             SetIndicators(context, output, itemList);
@@ -47,18 +48,17 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Carousel
 
         protected virtual void SetItems(TagHelperContext context, TagHelperOutput output, List<CarouselItem> itemList)
         {
-            var itemsHtml = new StringBuilder("");
-            itemsHtml.Append("<div class= \"carousel-inner\">");
+            var wrapper = new TagBuilder("div");
+            wrapper.AddCssClass("carousel-inner");
 
             foreach (var carouselItem in itemList)
             {
                 SetActiveIfActive(carouselItem);
 
-                itemsHtml.AppendLine(carouselItem.Html);
+                wrapper.InnerHtml.AppendHtml(carouselItem.Html);
             }
 
-            itemsHtml.Append("</div>");
-            output.Content.SetHtmlContent(itemsHtml.ToString());
+            output.Content.SetHtmlContent(wrapper);
         }
 
         protected virtual void SetControls(TagHelperContext context, TagHelperOutput output, List<CarouselItem> itemList)

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Collapse/AbpAccordionTagHelperService.cs

@@ -1,8 +1,8 @@
-using Microsoft.AspNetCore.Mvc.ViewFeatures;
+using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Mvc.ViewFeatures;
 using Microsoft.AspNetCore.Razor.TagHelpers;
 using System;
 using System.Collections.Generic;
-using System.Text;
 using System.Threading.Tasks;
 using Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.Microsoft.AspNetCore.Razor.TagHelpers;
 
@@ -30,26 +30,21 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Collapse
 
             await output.GetChildContentAsync();
 
-            var content = GetContent(items);
-
-            output.Content.SetHtmlContent(content);
+            ProcessItems(context, output, items);
         }
 
-        protected virtual string GetContent(List<string> items)
+        protected virtual void ProcessItems(TagHelperContext context, TagHelperOutput output, List<string> items)
         {
-            var html = new StringBuilder("");
             foreach (var item in items)
             {
                 var content = item.Replace(AbpAccordionParentIdPlaceholder, HtmlGenerator.Encode(TagHelper.Id));
 
-                html.AppendLine(
-                    "<div class=\"card\">" + Environment.NewLine + 
-                        content
-                    + "</div>" + Environment.NewLine
-                );
-            }
+                var wrapper = new TagBuilder("div");
+                wrapper.AddCssClass("card");
+                wrapper.InnerHtml.AppendHtml(content);
 
-            return html.ToString();
+                output.Content.AppendHtml(wrapper);
+            }
         }
 
         protected virtual List<string> InitilizeFormGroupContentsContext(TagHelperContext context, TagHelperOutput output)

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpInputTagHelperService.cs

@@ -1,12 +1,13 @@
-using System;
+using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Mvc.TagHelpers;
+using Microsoft.AspNetCore.Mvc.ViewFeatures;
+using Microsoft.AspNetCore.Razor.TagHelpers;
+using System;
 using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations;
 using System.Linq;
 using System.Text.Encodings.Web;
 using System.Threading.Tasks;
-using Microsoft.AspNetCore.Mvc.TagHelpers;
-using Microsoft.AspNetCore.Mvc.ViewFeatures;
-using Microsoft.AspNetCore.Razor.TagHelpers;
 using Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.Microsoft.AspNetCore.Razor.TagHelpers;
 using Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Extensions;
 
@@ -249,7 +250,7 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Form
         {
             if (IsOutputHidden(inputTag) || TagHelper.SuppressLabel)
             {
-                return "";
+                return string.Empty;
             }
 
             if (string.IsNullOrEmpty(TagHelper.Label))
@@ -257,11 +258,16 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Form
                 return await GetLabelAsHtmlUsingTagHelperAsync(context, output, isCheckbox) + GetRequiredSymbol(context, output);
             }
 
-            var checkboxClass = isCheckbox ? "class=\"custom-control-label\" " : "";
+            var label = new TagBuilder("label");
+            label.Attributes.Add("for", GetIdAttributeValue(inputTag));
+            label.InnerHtml.Append(TagHelper.Label);
+
+            if (isCheckbox)
+            {
+                label.AddCssClass("custom-control-label");
+            }
 
-            return "<label " + checkboxClass + GetIdAttributeAsString(inputTag) + ">"
-                   + TagHelper.Label +
-                   "</label>" + GetRequiredSymbol(context, output);
+            return RenderHtml(label);
         }
 
         protected virtual string GetRequiredSymbol(TagHelperContext context, TagHelperOutput output)
@@ -308,9 +314,11 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Form
             var idAttr = inputTag.Attributes.FirstOrDefault(a => a.Name == "id");
             var localizedText = _tagHelperLocalizer.GetLocalizedText(text, TagHelper.AspFor.ModelExplorer);
 
-            return "<small id=\"" + idAttr?.Value + "InfoText\" class=\"form-text text-muted\">" +
-                   localizedText +
-                   "</small>";
+            var small = new TagBuilder("small");
+            small.Attributes.Add("id", idAttr?.Value?.ToString() + "InfoText");
+            small.AddCssClass("form-text text-muted");
+
+            return RenderHtml(small);
         }
 
         protected virtual async Task<string> GetLabelAsHtmlUsingTagHelperAsync(TagHelperContext context, TagHelperOutput output, bool isCheckbox)
@@ -426,11 +434,11 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Form
             return inputTag.Attributes.Any(a => a.Name.ToLowerInvariant() == "type" && a.Value.ToString().ToLowerInvariant() == "hidden");
         }
 
-        protected virtual string GetIdAttributeAsString(TagHelperOutput inputTag)
+        protected virtual string GetIdAttributeValue(TagHelperOutput inputTag)
         {
             var idAttr = inputTag.Attributes.FirstOrDefault(a => a.Name == "id");
 
-            return idAttr != null ? "for=\"" + idAttr.Value + "\"" : "";
+            return idAttr != null ? idAttr.Value.ToString() : string.Empty;
         }
 
         protected virtual void AddGroupToFormGroupContents(TagHelperContext context, string propertyName, string html, int order, out bool suppress)

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpRadioInputTagHelperService.cs

@@ -1,12 +1,12 @@
+using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Mvc.ViewFeatures;
+using Microsoft.AspNetCore.Razor.TagHelpers;
+using Microsoft.Extensions.Localization;
 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
 using System.Text;
-using Microsoft.AspNetCore.Mvc.Rendering;
-using Microsoft.AspNetCore.Mvc.ViewFeatures;
-using Microsoft.AspNetCore.Razor.TagHelpers;
-using Microsoft.Extensions.Localization;
 using Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Extensions;
 
 namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Form
@@ -53,15 +53,35 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Form
                 var inlineClass = (TagHelper.Inline ?? false) ? " custom-control-inline" : "";
                 var id = TagHelper.AspFor.Name + "Radio" + selectItem.Value;
                 var name = TagHelper.AspFor.Name;
-                var selected = selectItem.Selected ? " checked=\"checked\"" : "";
-                var disabled = (TagHelper.Disabled??false) ? " disabled" : "";
 
-                var htmlPart = "<div class=\"custom-control custom-radio" + inlineClass + "\">\r\n" +
-                               "  <input type=\"radio\" id=\"" + id + "\" name=\"" + name + "\" value=\"" + selectItem.Value + "\"" + selected + " class=\"custom-control-input\""+ disabled + ">\r\n" +
-                               "  <label class=\"custom-control-label\" for=\"" + id + "\">" + selectItem.Text + "</label>\r\n" +
-                               "</div>";
+                var input = new TagBuilder("input");
+                input.AddCssClass("custom-control-input");
+                input.Attributes.Add("type", "radio");
+                input.Attributes.Add("id", id);
+                input.Attributes.Add("name", name);
+                input.Attributes.Add("value", selectItem.Value);
+
+                if (selectItem.Selected)
+                {
+                    input.Attributes.Add("checked", "checked");
+                }
+
+                if (TagHelper.Disabled ?? false)
+                {
+                    input.Attributes.Add("disabled", "disabled");
+                }
+
+                var label = new TagBuilder("label");
+                label.AddCssClass("custom-control-label");
+                label.Attributes.Add("for", id);
+                label.InnerHtml.Append(selectItem.Text);
+
+                var wrapper = new TagBuilder("div");
+                wrapper.AddCssClass("custom-control custom-radio" + inlineClass);
+                wrapper.InnerHtml.AppendHtml(input);
+                wrapper.InnerHtml.AppendHtml(label);
 
-                html.AppendLine(htmlPart);
+                html.AppendLine(RenderHtml(wrapper));
             }
 
             return html.ToString();

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Form/AbpSelectTagHelperService.cs

@@ -1,20 +1,18 @@
-using System;
+using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Mvc.TagHelpers;
+using Microsoft.AspNetCore.Mvc.ViewFeatures;
+using Microsoft.AspNetCore.Razor.TagHelpers;
+using Microsoft.Extensions.Localization;
+using System;
 using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations;
 using System.Linq;
 using System.Linq.Dynamic.Core;
 using System.Text.Encodings.Web;
 using System.Threading.Tasks;
-using Microsoft.AspNetCore.Mvc.Rendering;
-using Microsoft.AspNetCore.Mvc.TagHelpers;
-using Microsoft.AspNetCore.Mvc.ViewFeatures;
-using Microsoft.AspNetCore.Razor.TagHelpers;
-using Microsoft.Extensions.Localization;
 using Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.Microsoft.AspNetCore.Razor.TagHelpers;
 using Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Extensions;
-using Volo.Abp.DynamicProxy;
 using Volo.Abp.Localization;
-using Volo.Abp.Reflection;
 
 namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Form
 {
@@ -140,7 +138,11 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Form
         {
             if (!string.IsNullOrEmpty(TagHelper.Label))
             {
-                return "<label " + GetIdAttributeAsString(selectTag) + ">" + TagHelper.Label + "</label>" + GetRequiredSymbol(context, output);
+                var label = new TagBuilder("label");
+                label.Attributes.Add("for", GetIdAttributeValue(selectTag));
+                label.InnerHtml.Append(TagHelper.Label);
+
+                return RenderHtml(label) + GetRequiredSymbol(context, output);
             }
 
             return await GetLabelAsHtmlUsingTagHelperAsync(context, output) + GetRequiredSymbol(context, output);
@@ -199,9 +201,11 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Form
             var idAttr = inputTag.Attributes.FirstOrDefault(a => a.Name == "id");
             var localizedText = _tagHelperLocalizer.GetLocalizedText(text, TagHelper.AspFor.ModelExplorer);
 
-            return "<small id=\"" + idAttr?.Value + "InfoText\" class=\"form-text text-muted\">" +
-                   localizedText +
-                   "</small>";
+            var small = new TagBuilder("small");
+            small.Attributes.Add("id", idAttr?.Value?.ToString() + "InfoText");
+            small.AddCssClass("form-text text-muted");
+
+            return RenderHtml(small);
         }
 
         protected virtual List<SelectListItem> GetSelectItemsFromEnum(TagHelperContext context, TagHelperOutput output, ModelExplorer explorer)
@@ -338,11 +342,11 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Form
             }
         }
 
-        protected virtual string GetIdAttributeAsString(TagHelperOutput inputTag)
+        protected virtual string GetIdAttributeValue(TagHelperOutput inputTag)
         {
             var idAttr = inputTag.Attributes.FirstOrDefault(a => a.Name == "id");
 
-            return idAttr != null ? "for=\"" + idAttr.Value + "\"" : "";
+            return idAttr != null ? idAttr.Value.ToString() : string.Empty;
         }
 
         protected virtual void AddGroupToFormGroupContents(TagHelperContext context, string propertyName, string html, int order, out bool suppress)

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Modal/AbpModalFooterTagHelperService.cs

@@ -33,26 +33,26 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Modal
             switch (TagHelper.Buttons) 
             {
                 case AbpModalButtons.Cancel:
-                    output.PostContent.AppendHtml(GetCancelButton());
+                    AddCancelButton(context, output);
                     break;
                 case AbpModalButtons.Close:
-                    output.PostContent.AppendHtml(GetCloseButton());
+                    AddCloseButton(context, output);
                     break;
                 case AbpModalButtons.Save:
-                    output.PostContent.AppendHtml(GetSaveButton());
+                    AddSaveButton(context, output);
                     break;
                 case AbpModalButtons.Save | AbpModalButtons.Cancel:
-                    output.PostContent.AppendHtml(GetSaveButton());
-                    output.PostContent.AppendHtml(GetCancelButton());
+                    AddSaveButton(context, output);
+                    AddCancelButton(context, output);
                     break;
                 case AbpModalButtons.Save | AbpModalButtons.Close:
-                    output.PostContent.AppendHtml(GetSaveButton());
-                    output.PostContent.AppendHtml(GetCloseButton());
+                    AddSaveButton(context, output);
+                    AddCloseButton(context, output);
                     break;
             }
         }
 
-        protected virtual string GetSaveButton() 
+        protected virtual void AddSaveButton(TagHelperContext context, TagHelperOutput output) 
         {
             var icon = new TagBuilder("i");
             icon.AddCssClass("fa");
@@ -69,10 +69,10 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Modal
             button.InnerHtml.AppendHtml(icon);
             button.InnerHtml.AppendHtml(span);
 
-            return RenderHtml(button);
+            output.PostContent.AppendHtml(button);
         }
 
-        protected virtual string GetCloseButton() 
+        protected virtual void AddCloseButton(TagHelperContext context, TagHelperOutput output) 
         {
             var button = new TagBuilder("button");
             button.Attributes.Add("type", "button");
@@ -81,10 +81,10 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Modal
             button.AddCssClass("btn-secondary");
             button.InnerHtml.Append(_localizer["Close"]);
 
-            return RenderHtml(button);
+            output.PostContent.AppendHtml(button);
         }
 
-        protected virtual string GetCancelButton() 
+        protected virtual void AddCancelButton(TagHelperContext context, TagHelperOutput output) 
         {
             var button = new TagBuilder("button");
             button.Attributes.Add("type", "button");
@@ -93,7 +93,7 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Modal
             button.AddCssClass("btn-secondary");
             button.InnerHtml.Append(_localizer["Cancel"]);
 
-            return RenderHtml(button);
+            output.PostContent.AppendHtml(button);
         }
 
         protected virtual void ProcessButtonsAlignment(TagHelperOutput output)

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Modal/AbpModalHeaderTagHelperService.cs

@@ -1,38 +1,52 @@
-using Microsoft.AspNetCore.Mvc.Rendering;
+using Localization.Resources.AbpUi;
+using Microsoft.AspNetCore.Mvc.Rendering;
 using Microsoft.AspNetCore.Razor.TagHelpers;
-using System.Text;
+using Microsoft.Extensions.Localization;
 using Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.Microsoft.AspNetCore.Razor.TagHelpers;
 
 namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Modal
 {
     public class AbpModalHeaderTagHelperService : AbpTagHelperService<AbpModalHeaderTagHelper>
     {
+        protected IStringLocalizer<AbpUiResource> L { get; }
+
+        public AbpModalHeaderTagHelperService(IStringLocalizer<AbpUiResource> localizer)
+        {
+            L = localizer;
+        }
+
         public override void Process(TagHelperContext context, TagHelperOutput output)
         {
             output.TagName = "div";
             output.Attributes.AddClass("modal-header");
-            output.PreContent.SetHtmlContent(CreatePreContent());
-            output.PostContent.SetHtmlContent(CreatePostContent());
+
+            AddTitle(context, output);
+            AddCloseButton(context, output);
         }
 
-        protected virtual string CreatePreContent()
+        protected virtual void AddTitle(TagHelperContext context, TagHelperOutput output)
         {
             var title = new TagBuilder("h5");
             title.AddCssClass("modal-title");
             title.InnerHtml.Append(TagHelper.Title);
 
-            return RenderHtml(title);
+            output.PreContent.SetHtmlContent(title);
         }
 
-        protected virtual string CreatePostContent()
+        protected virtual void AddCloseButton(TagHelperContext context, TagHelperOutput output)
         {
-            var sb = new StringBuilder();
-            
-            sb.AppendLine("    <button type=\"button\" class=\"close\" data-dismiss=\"modal\" aria-label=\"Close\">");
-            sb.AppendLine("        <span aria-hidden=\"true\">&times;</span>");
-            sb.AppendLine("    </button>");
+            var span = new TagBuilder("span");
+            span.Attributes.Add("aria-hidden", "true");
+            span.InnerHtml.AppendHtml("&times;");
+
+            var button = new TagBuilder("button");
+            button.AddCssClass("close");
+            button.Attributes.Add("type", "button");
+            button.Attributes.Add("data-dismiss", "modal");
+            button.Attributes.Add("aria-label", L["Close"].Value);
+            button.InnerHtml.AppendHtml(span);
 
-            return sb.ToString();
+            output.PostContent.AppendHtml(button);
         }
     }
 }

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Modal/AbpModalTagHelperService.cs

@@ -1,40 +1,53 @@
-using Microsoft.AspNetCore.Mvc.ViewFeatures;
+using Microsoft.AspNetCore.Mvc.Rendering;
 using Microsoft.AspNetCore.Razor.TagHelpers;
-using System.Linq;
 using System.Text;
-
+using System.Threading.Tasks;
+
 namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Modal
 {
     public class AbpModalTagHelperService : AbpTagHelperService<AbpModalTagHelper>
-    {
-        protected IHtmlGenerator HtmlGenerator { get; }
-
-        public AbpModalTagHelperService(IHtmlGenerator htmlGenerator)
-        {
-            HtmlGenerator = htmlGenerator;
-        }
-
-        public override void Process(TagHelperContext context, TagHelperOutput output)
+    {
+        public override async Task ProcessAsync(TagHelperContext context, TagHelperOutput output)
         {
             output.TagName = null;
-            output.PreContent.SetHtmlContent(CreatePreContent(output));
-            output.PostContent.SetHtmlContent(CreatePostContent());
-        }
 
-        protected virtual string CreatePreContent(TagHelperOutput output)
-        {
-            var sb = new StringBuilder();
+            var childContent = await output.GetChildContentAsync();
 
-            var attritubutes = output.Attributes.Select(a => " " + HtmlGenerator.Encode(a.Name) + "=\"" + HtmlGenerator.Encode(a.Value) + "\" ").ToList();
-            var attritubutesAsJoin = string.Join(" ", attritubutes.ToArray());
-
-            sb.AppendLine("<div class=\"" + GetModalClasses() + "\" tabindex=\"-1\" role=\"dialog\" aria-hidden=\"true\" " + attritubutesAsJoin + GetDataAttributes() + ">");
-            sb.AppendLine("    <div class=\"" + GetModalDialogClasses() + "\" role=\"document\">");
-            sb.AppendLine("        <div class=\"" + GetModalContentClasses() + "\">");
-
-            return sb.ToString();
+            Process(context, output, childContent);
         }
 
+        protected virtual void Process(TagHelperContext context, TagHelperOutput output, TagHelperContent content)
+        {
+            var modalContent = new TagBuilder("div");
+            modalContent.AddCssClass(GetModalContentClasses());
+            modalContent.InnerHtml.AppendHtml(content);
+
+            var modalDialog = new TagBuilder("div");
+            modalDialog.AddCssClass(GetModalDialogClasses());
+            modalDialog.Attributes.Add("role", "document");
+            modalDialog.InnerHtml.AppendHtml(modalContent);
+
+            var modal = new TagBuilder("div");
+            modal.AddCssClass(GetModalClasses());
+            modal.Attributes.Add("tabindex", "-1");
+            modal.Attributes.Add("role", "dialog");
+            modal.Attributes.Add("aria-hidden", "true");
+
+            foreach (var attr in output.Attributes)
+            {
+                modal.Attributes.Add(attr.Name, attr.Value.ToString());
+            }
+
+            if (TagHelper.Static == true)
+            {
+                modal.Attributes.Add("data-backdrop", "static");
+            }
+
+            modal.InnerHtml.AppendHtml(modalDialog);
+
+            output.Content.SetHtmlContent(modal);
+        } 
+
         protected virtual string GetModalClasses()
         {
             return "modal fade";
@@ -63,25 +76,5 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Modal
         {
             return "modal-content";
         }
-
-        protected virtual string GetDataAttributes()
-        {
-            if (TagHelper.Static == true)
-            {
-                return "data-backdrop=\"static\" ";
-            }
-            return string.Empty;
-        }
-
-        protected virtual string CreatePostContent()
-        {
-            var sb = new StringBuilder();
-
-            sb.AppendLine("        </div>");
-            sb.AppendLine("    </div>");
-            sb.AppendLine("</div>");
-
-            return sb.ToString();
-        }
     }
 }

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Popover/AbpPopoverTagHelperService.cs

@@ -1,4 +1,5 @@
-using Microsoft.AspNetCore.Mvc.ViewFeatures;
+using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Mvc.ViewFeatures;
 using Microsoft.AspNetCore.Razor.TagHelpers;
 using System.Linq;
 
@@ -28,38 +29,51 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Popover
                 SetDisabled(context, output);
             }
         }
+
         protected virtual void SetDisabled(TagHelperContext context, TagHelperOutput output)
-        {
-            var triggerAsHtml = TagHelper.Dismissible ?? false ? "data-trigger=\"focus\" " : "";
+        {
+            var triggerValue = TagHelper.Dismissible ?? false ? "focus" : "";
             if (TagHelper.Hoverable ?? false)
             {
-                if (triggerAsHtml.Contains("focus"))
+                if (triggerValue.Contains("focus"))
                 {
-                    triggerAsHtml = triggerAsHtml.Replace("focus", "focus hover");
+                    triggerValue = triggerValue.Replace("focus", "focus hover");
                 }
                 else
                 {
-                    triggerAsHtml = "data-trigger=\"hover\" ";
+                    triggerValue = "hover";
                 }
-            }
-            var dataPlacementAsHtml = "data-placement=\"" + GetDirectory().ToString().ToLowerInvariant() + "\" ";
-
+            }
+
+            var dataPlacement = GetDirectory().ToString().ToLowerInvariant();
             // data-placement="default" with data-trigger="focus" causes Cannot read property 'indexOf' of undefined at computeAutoPlacement(bootstrap.bundle.js?_v=637146714627330435:2185) error
             if (IsDismissibleOrHoverable() && GetDirectory() == PopoverDirectory.Default)
             {
                 //dataPlacementAsHtml = string.Empty; //bootstrap default placement is right, abp's is top.
-                dataPlacementAsHtml = dataPlacementAsHtml.Replace("default", "top");
+                dataPlacement = dataPlacement.Replace("default", "top");
             }
+
             var titleAttribute = output.Attributes.FirstOrDefault(at => at.Name == "title");
-            var titleAsHtml = titleAttribute == null ? "" : "title=\"" + HtmlGenerator.Encode(titleAttribute.Value) + "\" ";
-            var preElementHtml = "<span tabindex=\"0\" class=\"d-inline-block\" " + titleAsHtml + triggerAsHtml + dataPlacementAsHtml + "data-toggle=\"popover\" data-content=\"" + HtmlGenerator.Encode(GetDataContent()) + "\">";
-            var postElementHtml = "</span>";
 
-            output.PreElement.SetHtmlContent(preElementHtml);
-            output.PostElement.SetHtmlContent(postElementHtml);
+            var span = new TagBuilder("span");
+            span.AddCssClass("d-inline-block");
+            span.Attributes.Add("tabindex", "0");
+            span.Attributes.Add("data-toggle", "popover");
+            span.Attributes.Add("data-content", GetDataContent());
+            span.Attributes.Add("data-trigger", triggerValue);
+            span.Attributes.Add("data-placement", dataPlacement);
+
+            if (titleAttribute != null)
+            {
+                span.Attributes.Add("title", titleAttribute.Value.ToString());
+            }
+
+            output.PreElement.SetHtmlContent(span.RenderStartTag());
+            output.PostElement.SetHtmlContent(span.RenderEndTag());
 
             output.Attributes.Add("style", "pointer-events: none;");
         }
+
         protected virtual void SetDataTriggerIfDismissible(TagHelperContext context, TagHelperOutput output)
         {
             if (TagHelper.Dismissible ?? false)

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Tab/AbpTabsTagHelperService.cs

@@ -1,9 +1,11 @@
-using System;
+using Microsoft.AspNetCore.Mvc.Rendering;
+using Microsoft.AspNetCore.Mvc.ViewFeatures;
+using Microsoft.AspNetCore.Razor.TagHelpers;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
-using Microsoft.AspNetCore.Razor.TagHelpers;
 using Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.Microsoft.AspNetCore.Razor.TagHelpers;
 using Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Grid;
 
@@ -11,6 +13,13 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Tab
 {
     public class AbpTabsTagHelperService : AbpTagHelperService<AbpTabsTagHelper>
     {
+        protected IHtmlGenerator HtmlGenerator { get; }
+
+        public AbpTabsTagHelperService(IHtmlGenerator htmlGenerator)
+        {
+            HtmlGenerator = htmlGenerator;
+        }
+
         public override async Task ProcessAsync(TagHelperContext context, TagHelperOutput output)
         {
             SetRandomNameIfNotProvided();
@@ -61,31 +70,34 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Tab
             var navClass = TagHelper.TabStyle == TabStyle.Tab ? " nav-tabs" : " nav-pills";
             var verticalClass = GetVerticalPillClassIfVertical();
 
-            var surroundedHeaders = "<ul class=\"nav" + verticalClass + navClass + "\" id=\"" + id + "\" role=\"tablist\">" + Environment.NewLine +
-                                   headers +
-                                   "</ul>";
+            var listElement = new TagBuilder("ul");
+            listElement.AddCssClass("nav" + verticalClass + navClass);
+            listElement.Attributes.Add("id", id);
+            listElement.Attributes.Add("role", "tablist");
+            listElement.InnerHtml.AppendHtml(headers);
 
-            return surroundedHeaders;
+            return RenderHtml(listElement);
         }
 
         protected virtual string SurroundContents(TagHelperContext context, TagHelperOutput output, string contents)
         {
             var id = TagHelper.Name + "Content";
 
-            var surroundedContents = "<div class=\"tab-content\" id=\"" + id + "\">" + Environment.NewLine +
-                                   contents +
-                                   "   </div>";
+            var wrapper = new TagBuilder("div");
+            wrapper.AddCssClass("tab-content");
+            wrapper.Attributes.Add("id", id);
+            wrapper.InnerHtml.AppendHtml(contents);
 
-            return surroundedContents;
+            return RenderHtml(wrapper);
         }
 
         protected virtual string PlaceInsideColumn(string contents, int columnSize)
         {
-            var surroundedContents = "<div class=\"col-md-" + columnSize + "\">" + Environment.NewLine +
-                                   contents +
-                                   "   </div>";
+            var wrapper = new TagBuilder("div");
+            wrapper.AddCssClass("col-md-" + columnSize);
+            wrapper.InnerHtml.AppendHtml(contents);
 
-            return surroundedContents;
+            return RenderHtml(wrapper);
         }
 
         protected virtual void PlaceInsideRow(TagHelperOutput output)
@@ -213,7 +225,7 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Tab
 
         protected virtual string SetTabItemNameIfNotProvided(string content, int index)
         {
-            return content.Replace(TabItemNamePlaceHolder, TagHelper.Name + "_" + index);
+            return content.Replace(TabItemNamePlaceHolder, HtmlGenerator.Encode(TagHelper.Name) + "_" + index);
         }
     }
 }

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Bootstrap/TagHelpers/Tooltip/AbpTooltipTagHelperService.cs

@@ -1,19 +1,11 @@
-using System;
-using System.Linq;
-using Microsoft.AspNetCore.Mvc.ViewFeatures;
+using Microsoft.AspNetCore.Mvc.Rendering;
 using Microsoft.AspNetCore.Razor.TagHelpers;
+using System.Linq;
 
 namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Tooltip
 {
     public class AbpTooltipTagHelperService : AbpTagHelperService<AbpTooltipTagHelper>
     {
-        protected IHtmlGenerator HtmlGenerator { get; }
-
-        public AbpTooltipTagHelperService(IHtmlGenerator htmlGenerator)
-        {
-            HtmlGenerator = htmlGenerator;
-        }
-
         public override void Process(TagHelperContext context, TagHelperOutput output)
         {
             if (IsButtonDisabled(context, output))
@@ -32,12 +24,16 @@ namespace Volo.Abp.AspNetCore.Mvc.UI.Bootstrap.TagHelpers.Tooltip
             var directory = GetDirectory() != TooltipDirectory.Default ? GetDirectory() : TooltipDirectory.Top;
             output.Attributes.Add("data-placement", directory.ToString().ToLowerInvariant());
 
-            output.PreElement.SetHtmlContent(
-                "<span class=\"d-inline-block\" tabindex=\"0\" data-toggle=\"tooltip\" " +
-                "data-placement=\"" + HtmlGenerator.Encode(directory.ToString().ToLowerInvariant()) +
-                "\" title=\"" + HtmlGenerator.Encode(GetTitle()) + "\">" + Environment.NewLine);
+            var span = new TagBuilder("span");
+            span.AddCssClass("d-inline-block");
+            span.Attributes.Add("tabindex", "0");
+            span.Attributes.Add("data-toggle", "tooltip");
+            span.Attributes.Add("data-placement", directory.ToString().ToLowerInvariant());
+            span.Attributes.Add("title", GetTitle());
+
+            output.PreElement.SetHtmlContent(span.RenderStartTag());
 
-            output.PostElement.SetHtmlContent(Environment.NewLine + "</span>");
+            output.PostElement.SetHtmlContent(span.RenderEndTag());
 
             output.Attributes.Add("style", "pointer-events: none;");
         }