Assembly : mscorlib (dans mscorlib.dll)
Syntaxe<ComVisibleAttribute(True)> _ <CLSCompliantAttribute(False)> _ Public Interface IConvertible
Dim instance As IConvertible
[ComVisibleAttribute(true)] [CLSCompliantAttribute(false)] public interface IConvertible
[ComVisibleAttribute(true)] [CLSCompliantAttribute(false)] public interface class IConvertible
/** @attribute ComVisibleAttribute(true) */ /** @attribute CLSCompliantAttribute(false) */ public interface IConvertible
ComVisibleAttribute(true) CLSCompliantAttribute(false) public interface IConvertible
NotesCette interface fournit des méthodes permettant de convertir la valeur d'une instance d'un type d'implémentation en un type Common Language Runtime possédant une valeur équivalente. Les types Common Language Runtime sont les suivants : Boolean, SByte, Byte, Int16, UInt16, Int32, UInt32, Int64, UInt64, Single, Double, Decimal, DateTime, Char et String.
S'il n'existe aucune conversion significative en un type Common Language Runtime, l'implémentation d'une méthode d'interface particulière lève InvalidCastException. Par exemple, si cette interface est implémentée sur un type booléen, l'implémentation de la méthode ToDateTime lève une exception, car il n'existe aucun équivalent DateTime significatif pour un type booléen.
Le Common Language Runtime expose généralement l'interface IConvertible par l'intermédiaire de la classe Convert. Le Common Language Runtime utilise également l'interface IConvertible en interne, dans des implémentations d'interface explicites afin de simplifier le code employé pour la prise en charge des conversions dans la classe Convert et dans les types Common Language Runtime de base.
Outre l'interface IConvertible, le .NET Framework fournit des classes appelées convertisseurs de type pour la conversion de types de données définis par l'utilisateur en d'autres types de données. Pour plus d'informations, consultez la rubrique Conversion de type généralisée.
ExempleL'exemple de code suivant illustre une implémentation de IConvertible pour une classe de nombres complexes, en lui permettant d'être d'abord casté en Double puis en appelant ensuite les membres Convert statiques sur Double.
Imports System Module Module1 Public Class Complex Implements IConvertible Private x As Double Private y As Double Public Sub New(ByVal x As Double, ByVal y As Double) Me.x = x Me.y = y End Sub 'New Public Function GetTypeCode() As TypeCode Implements IConvertible.GetTypeCode Return TypeCode.Object End Function Function ToBoolean(ByVal provider As IFormatProvider) As Boolean Implements IConvertible.ToBoolean If x <> 0 Or y <> 0 Then Return True Else Return False End If End Function Function GetDoubleValue() As Double Return Math.Sqrt((x * x + y * y)) End Function Function ToByte(ByVal provider As IFormatProvider) As Byte Implements IConvertible.ToByte Return Convert.ToByte(GetDoubleValue()) End Function Function ToChar(ByVal provider As IFormatProvider) As Char Implements IConvertible.ToChar Return Convert.ToChar(GetDoubleValue()) End Function Function ToDateTime(ByVal provider As IFormatProvider) As DateTime Implements IConvertible.ToDateTime Return Convert.ToDateTime(GetDoubleValue()) End Function Function ToDecimal(ByVal provider As IFormatProvider) As Decimal Implements IConvertible.ToDecimal Return Convert.ToDecimal(GetDoubleValue()) End Function Function ToDouble(ByVal provider As IFormatProvider) As Double Implements IConvertible.ToDouble Return GetDoubleValue() End Function Function ToInt16(ByVal provider As IFormatProvider) As Short Implements IConvertible.ToInt16 Return Convert.ToInt16(GetDoubleValue()) End Function Function ToInt32(ByVal provider As IFormatProvider) As Integer Implements IConvertible.ToInt32 Return Convert.ToInt32(GetDoubleValue()) End Function Function ToInt64(ByVal provider As IFormatProvider) As Long Implements IConvertible.ToInt64 Return Convert.ToInt64(GetDoubleValue()) End Function Function ToSByte(ByVal provider As IFormatProvider) As SByte Implements IConvertible.ToSByte Return Convert.ToSByte(GetDoubleValue()) End Function Function ToSingle(ByVal provider As IFormatProvider) As Single Implements IConvertible.ToSingle Return Convert.ToSingle(GetDoubleValue()) End Function Overloads Function ToString(ByVal provider As IFormatProvider) As String Implements IConvertible.ToString Return "( " + x.ToString() + " , " + y.ToString() + " )" End Function Function ToType(ByVal conversionType As Type, ByVal provider As IFormatProvider) As Object Implements IConvertible.ToType Return Convert.ChangeType(GetDoubleValue(), conversionType) End Function Function ToUInt16(ByVal provider As IFormatProvider) As UInt16 Implements IConvertible.ToUInt16 Return Convert.ToUInt16(GetDoubleValue()) End Function Function ToUInt32(ByVal provider As IFormatProvider) As UInt32 Implements IConvertible.ToUInt32 Return Convert.ToUInt32(GetDoubleValue()) End Function Function ToUInt64(ByVal provider As IFormatProvider) As UInt64 Implements IConvertible.ToUInt64 Return Convert.ToUInt64(GetDoubleValue()) End Function End Class Sub Main() Dim testComplex As New Complex(4, 7) WriteObjectInfo(testComplex) WriteObjectInfo(Convert.ToBoolean(testComplex)) WriteObjectInfo(Convert.ToDecimal(testComplex)) WriteObjectInfo(Convert.ToString(testComplex)) End Sub Sub WriteObjectInfo(ByVal testObject As Object) Dim typeCode As TypeCode = Type.GetTypeCode(testObject.GetType()) Select Case typeCode Case typeCode.Boolean Console.WriteLine("Boolean: {0}", testObject) Case typeCode.Double Console.WriteLine("Double: {0}", testObject) Case Else Console.WriteLine("{0}: {1}", typeCode.ToString(), testObject) End Select End Sub End Module
using System; namespace ConsoleApplication2 { /// Class that implements IConvertible class Complex : IConvertible { double x; double y; public Complex(double x, double y) { this.x = x; this.y = y; } public TypeCode GetTypeCode() { return TypeCode.Object; } bool IConvertible.ToBoolean(IFormatProvider provider) { if( (x != 0.0) || (y != 0.0) ) return true; else return false; } double GetDoubleValue() { return Math.Sqrt(x*x + y*y); } byte IConvertible.ToByte(IFormatProvider provider) { return Convert.ToByte(GetDoubleValue()); } char IConvertible.ToChar(IFormatProvider provider) { return Convert.ToChar(GetDoubleValue()); } DateTime IConvertible.ToDateTime(IFormatProvider provider) { return Convert.ToDateTime(GetDoubleValue()); } decimal IConvertible.ToDecimal(IFormatProvider provider) { return Convert.ToDecimal(GetDoubleValue()); } double IConvertible.ToDouble(IFormatProvider provider) { return GetDoubleValue(); } short IConvertible.ToInt16(IFormatProvider provider) { return Convert.ToInt16(GetDoubleValue()); } int IConvertible.ToInt32(IFormatProvider provider) { return Convert.ToInt32(GetDoubleValue()); } long IConvertible.ToInt64(IFormatProvider provider) { return Convert.ToInt64(GetDoubleValue()); } sbyte IConvertible.ToSByte(IFormatProvider provider) { return Convert.ToSByte(GetDoubleValue()); } float IConvertible.ToSingle(IFormatProvider provider) { return Convert.ToSingle(GetDoubleValue()); } string IConvertible.ToString(IFormatProvider provider) { return "( " + x.ToString() + " , " + y.ToString() + " )"; } object IConvertible.ToType(Type conversionType, IFormatProvider provider) { return Convert.ChangeType(GetDoubleValue(),conversionType); } ushort IConvertible.ToUInt16(IFormatProvider provider) { return Convert.ToUInt16(GetDoubleValue()); } uint IConvertible.ToUInt32(IFormatProvider provider) { return Convert.ToUInt32(GetDoubleValue()); } ulong IConvertible.ToUInt64(IFormatProvider provider) { return Convert.ToUInt64(GetDoubleValue()); } } /// <summary> /// Summary description for Class1. /// </summary> class Class1 { static void Main(string[] args) { Complex testComplex = new Complex(4,7); WriteObjectInfo(testComplex); WriteObjectInfo(Convert.ToBoolean(testComplex)); WriteObjectInfo(Convert.ToDecimal(testComplex)); WriteObjectInfo(Convert.ToString(testComplex)); } static void WriteObjectInfo(object testObject) { TypeCode typeCode = Type.GetTypeCode( testObject.GetType() ); switch( typeCode ) { case TypeCode.Boolean: Console.WriteLine("Boolean: {0}", testObject); break; case TypeCode.Double: Console.WriteLine("Double: {0}", testObject); break; default: Console.WriteLine("{0}: {1}", typeCode.ToString(), testObject); break; } } } }
#using <System.dll> using namespace System; /// Class that implements IConvertible ref class Complex: public IConvertible { private: double x; double y; public: Complex( double x, double y ) { this->x = x; this->y = y; } virtual TypeCode GetTypeCode() { return TypeCode::Object; } virtual bool ToBoolean( IFormatProvider^ /*provider*/ ) = IConvertible::ToBoolean { if ( (x != 0.0) || (y != 0.0) ) return true; else return false; } double GetDoubleValue() { return Math::Sqrt( x * x + y * y ); } virtual Byte ToByte( IFormatProvider^ /*provider*/ ) = IConvertible::ToByte { return Convert::ToByte( GetDoubleValue() ); } virtual Char ToChar( IFormatProvider^ /*provider*/ ) = IConvertible::ToChar { return Convert::ToChar( GetDoubleValue() ); } virtual DateTime ToDateTime( IFormatProvider^ /*provider*/ ) = IConvertible::ToDateTime { return Convert::ToDateTime( GetDoubleValue() ); } virtual Decimal ToDecimal( IFormatProvider^ /*provider*/ ) = IConvertible::ToDecimal { return Convert::ToDecimal( GetDoubleValue() ); } virtual double ToDouble( IFormatProvider^ /*provider*/ ) = IConvertible::ToDouble { return GetDoubleValue(); } virtual short ToInt16( IFormatProvider^ /*provider*/ ) = IConvertible::ToInt16 { return Convert::ToInt16( GetDoubleValue() ); } virtual int ToInt32( IFormatProvider^ /*provider*/ ) = IConvertible::ToInt32 { return Convert::ToInt32( GetDoubleValue() ); } virtual Int64 ToInt64( IFormatProvider^ /*provider*/ ) = IConvertible::ToInt64 { return Convert::ToInt64( GetDoubleValue() ); } virtual signed char ToSByte( IFormatProvider^ /*provider*/ ) = IConvertible::ToSByte { return Convert::ToSByte( GetDoubleValue() ); } virtual float ToSingle( IFormatProvider^ /*provider*/ ) = IConvertible::ToSingle { return Convert::ToSingle( GetDoubleValue() ); } virtual String^ ToString( IFormatProvider^ /*provider*/ ) = IConvertible::ToString { return String::Format( "( {0} , {1} )", x, y ); } virtual Object^ ToType( Type^ conversionType, IFormatProvider^ /*provider*/ ) = IConvertible::ToType { return Convert::ChangeType( GetDoubleValue(), conversionType ); } virtual UInt16 ToUInt16( IFormatProvider^ /*provider*/ ) = IConvertible::ToUInt16 { return Convert::ToUInt16( GetDoubleValue() ); } virtual UInt32 ToUInt32( IFormatProvider^ /*provider*/ ) = IConvertible::ToUInt32 { return Convert::ToUInt32( GetDoubleValue() ); } virtual UInt64 ToUInt64( IFormatProvider^ /*provider*/ ) = IConvertible::ToUInt64 { return Convert::ToUInt64( GetDoubleValue() ); } }; void WriteObjectInfo( Object^ testObject ) { TypeCode typeCode = Type::GetTypeCode( testObject->GetType() ); switch ( typeCode ) { case TypeCode::Boolean: Console::WriteLine( "Boolean: {0}", testObject ); break; case TypeCode::Double: Console::WriteLine( "Double: {0}", testObject ); break; default: Console::WriteLine( "{0}: {1}", typeCode, testObject ); break; } } int main() { Complex^ testComplex = gcnew Complex( 4,7 ); WriteObjectInfo( testComplex ); WriteObjectInfo( Convert::ToBoolean( testComplex ) ); WriteObjectInfo( Convert::ToDecimal( testComplex ) ); WriteObjectInfo( Convert::ToString( testComplex ) ); }
package ConsoleApplication2 ; import System.*; /// Class that implements IConvertible class Complex implements IConvertible { private double x; private double y; public Complex(double x, double y) { this.x = x; this.y = y; } //Complex public TypeCode GetTypeCode() { return TypeCode.Object; } //GetTypeCode public boolean ToBoolean(IFormatProvider provider) { if (x != 0.0 || y != 0.0) { return true; } else { return false; } } //ToBoolean double GetDoubleValue() { return System.Math.Sqrt((x * x + y * y)); } //GetDoubleValue public ubyte ToByte(IFormatProvider provider) { return Convert.ToByte(GetDoubleValue()); } //ToByte public char ToChar(IFormatProvider provider) { return Convert.ToChar(GetDoubleValue()); } //ToChar public DateTime ToDateTime(IFormatProvider provider) { return Convert.ToDateTime(GetDoubleValue()); } //ToDateTime public System.Decimal ToDecimal(IFormatProvider provider) { return Convert.ToDecimal(GetDoubleValue()); } //ToDecimal public double ToDouble(IFormatProvider provider) { return GetDoubleValue(); } //ToDouble public short ToInt16(IFormatProvider provider) { return Convert.ToInt16(GetDoubleValue()); } //ToInt16 public int ToInt32(IFormatProvider provider) { return Convert.ToInt32(GetDoubleValue()); } //ToInt32 public long ToInt64(IFormatProvider provider) { return Convert.ToInt64(GetDoubleValue()); } //ToInt64 public byte ToSByte(IFormatProvider provider) { return Convert.ToSByte(GetDoubleValue()); } //ToSByte public float ToSingle(IFormatProvider provider) { return Convert.ToSingle(GetDoubleValue()); } //ToSingle public String ToString(IFormatProvider provider) { return "( " + System.Convert.ToString(x) + " , " + System.Convert.ToString(y)+ " )"; } //ToString public Object ToType(Type conversionType, IFormatProvider provider) { return Convert.ChangeType(new Double(GetDoubleValue()), conversionType); } //ToType public UInt16 ToUInt16(IFormatProvider provider) { return Convert.ToUInt16(GetDoubleValue()); } //ToUInt16 public UInt32 ToUInt32(IFormatProvider provider) { return Convert.ToUInt32(GetDoubleValue()); } //ToUInt32 public UInt64 ToUInt64(IFormatProvider provider) { return Convert.ToUInt64(GetDoubleValue()); } //ToUInt64 } //Complex /// <summary> /// Summary description for Class1. /// </summary> class Class1 { public static void main(String[] args) { Complex testComplex = new Complex(4, 7); WriteObjectInfo(testComplex); WriteObjectInfo((System.Boolean)(Convert.ToBoolean(testComplex))); WriteObjectInfo(Convert.ToDecimal(testComplex)); WriteObjectInfo(Convert.ToString(testComplex)); } //main static void WriteObjectInfo(Object testObject) { TypeCode typeCode = Type.GetTypeCode(testObject.GetType()); switch (typeCode) { case TypeCode.Boolean : Console.WriteLine("Boolean: {0}", testObject); break; case TypeCode.Double : Console.WriteLine("Double: {0}", testObject); break; default : Console.WriteLine("{0}: {1}", typeCode.ToString(), testObject); break; } } //WriteObjectInfo } //Class1
Plates-formesWindows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile pour Pocket PC, Windows Mobile pour Smartphone, Windows Server 2003, Windows XP Édition Media Center, Windows XP Professionnel Édition x64, Windows XP SP2, Windows XP Starter Edition
Le .NET Framework ne prend pas en charge toutes les versions de chaque plate-forme. Pour obtenir la liste des versions prises en charge, consultez Configuration requise.
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