@ -14,17 +14,61 @@ namespace Avalonia.Utilities
/// </summary>
public static class TypeUtilities
{
private static readonly Dictionary < Type , List < Type > > Conversions = new Dictionary < Type , List < Type > > ( )
private static int [ ] Conversions =
{
{ typeof ( decimal ) , new List < Type > { typeof ( sbyte ) , typeof ( byte ) , typeof ( short ) , typeof ( ushort ) , typeof ( int ) , typeof ( uint ) , typeof ( long ) , typeof ( ulong ) , typeof ( char ) } } ,
{ typeof ( double ) , new List < Type > { typeof ( sbyte ) , typeof ( byte ) , typeof ( short ) , typeof ( ushort ) , typeof ( int ) , typeof ( uint ) , typeof ( long ) , typeof ( ulong ) , typeof ( char ) , typeof ( float ) } } ,
{ typeof ( float ) , new List < Type > { typeof ( sbyte ) , typeof ( byte ) , typeof ( short ) , typeof ( ushort ) , typeof ( int ) , typeof ( uint ) , typeof ( long ) , typeof ( ulong ) , typeof ( char ) , typeof ( float ) } } ,
{ typeof ( ulong ) , new List < Type > { typeof ( byte ) , typeof ( ushort ) , typeof ( uint ) , typeof ( char ) } } ,
{ typeof ( long ) , new List < Type > { typeof ( sbyte ) , typeof ( byte ) , typeof ( short ) , typeof ( ushort ) , typeof ( int ) , typeof ( uint ) , typeof ( char ) } } ,
{ typeof ( uint ) , new List < Type > { typeof ( byte ) , typeof ( ushort ) , typeof ( char ) } } ,
{ typeof ( int ) , new List < Type > { typeof ( sbyte ) , typeof ( byte ) , typeof ( short ) , typeof ( ushort ) , typeof ( char ) } } ,
{ typeof ( ushort ) , new List < Type > { typeof ( byte ) , typeof ( char ) } } ,
{ typeof ( short ) , new List < Type > { typeof ( byte ) } }
0 b101111111111101 , // Boolean
0 b100001111111110 , // Char
0 b101111111111111 , // SByte
0 b101111111111111 , // Byte
0 b101111111111111 , // Int16
0 b101111111111111 , // UInt16
0 b101111111111111 , // Int32
0 b101111111111111 , // UInt32
0 b101111111111111 , // Int64
0 b101111111111111 , // UInt64
0 b101111111111101 , // Single
0 b101111111111101 , // Double
0 b101111111111101 , // Decimal
0 b110000000000000 , // DateTime
0 b111111111111111 , // String
} ;
private static int [ ] ImplicitConversions =
{
0 b000000000000001 , // Boolean
0 b001110111100010 , // Char
0 b001110101010100 , // SByte
0 b001111111111000 , // Byte
0 b001110101010000 , // Int16
0 b001111111100000 , // UInt16
0 b001110101000000 , // Int32
0 b001111110000000 , // UInt32
0 b001110100000000 , // Int64
0 b001111000000000 , // UInt64
0 b000110000000000 , // Single
0 b000100000000000 , // Double
0 b001000000000000 , // Decimal
0 b010000000000000 , // DateTime
0 b100000000000000 , // String
} ;
private static Type [ ] InbuiltTypes =
{
typeof ( Boolean ) ,
typeof ( Char ) ,
typeof ( SByte ) ,
typeof ( Byte ) ,
typeof ( Int16 ) ,
typeof ( UInt16 ) ,
typeof ( Int32 ) ,
typeof ( UInt32 ) ,
typeof ( Int64 ) ,
typeof ( UInt64 ) ,
typeof ( Single ) ,
typeof ( Double ) ,
typeof ( Decimal ) ,
typeof ( DateTime ) ,
typeof ( String ) ,
} ;
private static readonly Type [ ] NumericTypes = new [ ]
@ -54,49 +98,104 @@ namespace Avalonia.Utilities
}
/// <summary>
/// Try to cast a value to a type, using implicit conversions if possible.
/// Try to convert a value to a type by any means possible.
/// </summary>
/// <param name="to">The type to cast to.</param>
/// <param name="value">The value to cast.</param>
/// <param name="culture">The culture to use.</param>
/// <param name="result">If sucessful, contains the cast value.</param>
/// <returns>True if the cast was sucessful, otherwise false.</returns>
public static bool TryCas t ( Type to , object value , out object result )
public static bool TryConver t ( Type to , object value , CultureInfo cultur e , out object result )
{
Contract . Requires < ArgumentNullException > ( to ! = null ) ;
if ( value = = null )
{
result = null ;
return AcceptsNull ( to ) ;
}
var from = value . GetType ( ) ;
if ( value = = AvaloniaProperty . UnsetValue )
{
result = value ;
return true ;
}
else if ( to . GetTypeInfo ( ) . IsAssignableFrom ( from . GetTypeInfo ( ) ) )
var from = value . GetType ( ) ;
var fromTypeInfo = from . GetTypeInfo ( ) ;
var toTypeInfo = to . GetTypeInfo ( ) ;
if ( toTypeInfo . IsAssignableFrom ( fromTypeInfo ) )
{
result = value ;
return true ;
}
else if ( Conversions . ContainsKey ( to ) & & Conversions [ to ] . Contains ( from ) )
if ( to = = typeof ( string ) )
{
result = Convert . ChangeType ( value , to ) ;
result = Convert . ToString ( value ) ;
return true ;
}
else
if ( toTypeInfo . IsEnum & & from = = typeof ( string ) )
{
if ( Enum . IsDefined ( to , ( string ) value ) )
{
result = Enum . Parse ( to , ( string ) value ) ;
return true ;
}
}
if ( ! fromTypeInfo . IsEnum & & toTypeInfo . IsEnum )
{
var cast = from . GetRuntimeMethods ( )
. FirstOrDefault ( m = > m . Name = = "op_Implicit" & & m . ReturnType = = to ) ;
result = null ;
if ( TryConvert ( Enum . GetUnderlyingType ( to ) , value , culture , out object enumValue ) )
{
result = Enum . ToObject ( to , enumValue ) ;
return true ;
}
}
if ( cast ! = null )
if ( fromTypeInfo . IsEnum & & IsNumeric ( to ) )
{
try
{
result = cast . Invoke ( null , new [ ] { value } ) ;
result = Convert . ChangeType ( ( int ) value , to , culture ) ;
return true ;
}
catch
{
result = null ;
return false ;
}
}
var convertableFrom = Array . IndexOf ( InbuiltTypes , from ) ;
var convertableTo = Array . IndexOf ( InbuiltTypes , to ) ;
if ( convertableFrom ! = - 1 & & convertableTo ! = - 1 )
{
if ( ( Conversions [ convertableFrom ] & 1 < < convertableTo ) ! = 0 )
{
try
{
result = Convert . ChangeType ( value , to , culture ) ;
return true ;
}
catch
{
result = null ;
return false ;
}
}
}
var cast = from . GetRuntimeMethods ( )
. FirstOrDefault ( m = > ( m . Name = = "op_Implicit" | | m . Name = = "op_Explicit" ) & & m . ReturnType = = to ) ;
if ( cast ! = null )
{
result = cast . Invoke ( null , new [ ] { value } ) ;
return true ;
}
result = null ;
@ -104,15 +203,14 @@ namespace Avalonia.Utilities
}
/// <summary>
/// Try to convert a value to a type, using <see cref="System.Convert"/> if possible,
/// otherwise using <see cref="TryCast(Type, object, out object)"/> .
/// Try to convert a value to a type using the implicit conversions allowed by the C#
/// language .
/// </summary>
/// <param name="to">The type to cast to.</param>
/// <param name="value">The value to cast.</param>
/// <param name="culture">The culture to use.</param>
/// <param name="result">If sucessful, contains the cast value.</param>
/// <returns>True if the cast was sucessful, otherwise false.</returns>
public static bool TryConvert ( Type to , object value , CultureInfo cultur e , out object result )
public static bool TryConvertImplicit ( Type to , object value , out object result )
{
if ( value = = null )
{
@ -120,54 +218,44 @@ namespace Avalonia.Utilities
return AcceptsNull ( to ) ;
}
var from = value . GetType ( ) ;
if ( value = = AvaloniaProperty . UnsetValue )
{
result = value ;
return true ;
}
if ( to . GetTypeInfo ( ) . IsAssignableFrom ( from . GetTypeInfo ( ) ) )
{
result = value ;
return true ;
}
var from = value . GetType ( ) ;
var fromTypeInfo = from . GetTypeInfo ( ) ;
var toTypeInfo = to . GetTypeInfo ( ) ;
if ( to = = typeof ( string ) )
if ( toTypeInfo . IsAssignableFrom ( fromTypeInfo ) )
{
result = Convert . ToString ( value ) ;
result = value ;
return true ;
}
if ( to . GetTypeInfo ( ) . IsEnum & & from = = typeof ( string ) )
{
if ( Enum . IsDefined ( to , ( string ) value ) )
{
result = Enum . Parse ( to , ( string ) value ) ;
return true ;
}
}
bool containsFrom = Conversions . ContainsKey ( from ) ;
bool containsTo = Conversions . ContainsKey ( to ) ;
var convertableFrom = Array . IndexOf ( InbuiltTypes , from ) ;
var convertableTo = Array . IndexOf ( InbuiltTypes , to ) ;
if ( ( containsFrom & & containsTo ) | | ( from = = typeof ( string ) & & containsTo ) )
if ( convertableFrom ! = - 1 & & convertableTo ! = - 1 )
{
try
{
result = Convert . ChangeType ( value , to , culture ) ;
return true ;
}
catch
if ( ( ImplicitConversions [ convertableFrom ] & 1 < < convertableTo ) ! = 0 )
{
result = null ;
return false ;
try
{
result = Convert . ChangeType ( value , to , CultureInfo . InvariantCulture ) ;
return true ;
}
catch
{
result = null ;
return false ;
}
}
}
var cast = from . GetRuntimeMethods ( )
. FirstOrDefault ( m = > ( m . Name = = "op_Implicit" | | m . Name = = "op_Explicit" ) & & m . ReturnType = = to ) ;
. FirstOrDefault ( m = > m . Name = = "op_Implicit" & & m . ReturnType = = to ) ;
if ( cast ! = null )
{
@ -180,29 +268,28 @@ namespace Avalonia.Utilities
}
/// <summary>
/// Casts a value to a type, returning the default for that type if the value could not b e
/// cast .
/// Convert a value to a type by any means possible, returning the default for that typ e
/// if the value could not be converted .
/// </summary>
/// <param name="value">The value to cast.</param>
/// <param name="type">The type to cast to..</param>
/// <param name="culture">The culture to use.</param>
/// <returns>A value of <paramref name="type"/>.</returns>
public static object Cas tOrDefault ( object value , Type type )
public static object Conver tOrDefault ( object value , Type type , CultureInfo cultur e )
{
var typeInfo = type . GetTypeInfo ( ) ;
object result ;
return TryConvert ( type , value , culture , out object result ) ? result : Default ( type ) ;
}
if ( TypeUtilities . TryCast ( type , value , out result ) )
{
return result ;
}
else if ( typeInfo . IsValueType )
{
return Activator . CreateInstance ( type ) ;
}
else
{
return null ;
}
/// <summary>
/// Convert a value to a type using the implicit conversions allowed by the C# language or
/// return the default for the type if the value could not be converted.
/// </summary>
/// <param name="value">The value to cast.</param>
/// <param name="type">The type to cast to..</param>
/// <returns>A value of <paramref name="type"/>.</returns>
public static object ConvertImplicitOrDefault ( object value , Type type )
{
return TryConvertImplicit ( type , value , out object result ) ? result : Default ( type ) ;
}
/// <summary>
Jeremy Koritzinsky
9 years ago
GitHub