VB.NET Decimal.Explicit操作符代码示例

' Example of the explicit conversion from Single to Decimal.
Module DecimalFromSingleDemo

    Const formatter As String = "{0,16:E7}{1,33}"
 
    ' Get the exception type name; remove the namespace prefix.
    Function GetExceptionType( ex As Exception ) As String

        Dim exceptionType   As String = ex.GetType( ).ToString( )
        Return exceptionType.Substring( _
            exceptionType.LastIndexOf( "."c ) + 1 )
    End Function

    ' Convert the Single argument; catch exceptions that are thrown.
    Sub DecimalFromSingle( argument As Single )

        Dim decValue    As Object
          
        ' Convert the Single argument to a Decimal value.
        Try
            decValue = Decimal.op_Explicit( argument )
        Catch ex As Exception
            decValue = GetExceptionType( ex )
        End Try

        ' Display the Decimal.
        Console.WriteLine( formatter, argument, decValue )
    End Sub 
       
    Sub Main( )

        Console.WriteLine( _
            "This example of the explicit conversion from Single " & _
            "to Decimal " & vbCrLf & "generates the following " & _
            "output." & vbCrLf )
        Console.WriteLine( formatter, "Single argument", _
            "Decimal value" )
        Console.WriteLine( formatter, "---------------", _
            "-------------" )
          
        ' Convert Single values and display the results.
        DecimalFromSingle( 1.2345E-30 )
        DecimalFromSingle( 1.2345E-26 )
        DecimalFromSingle( 1.23456E-22 )
        DecimalFromSingle( 1.23456E-12 )
        DecimalFromSingle( 1.234567 )
        DecimalFromSingle( 1.234567E+12 )
        DecimalFromSingle( 1.2345678E+28 ) 
        DecimalFromSingle( 1.2345678E+30 )
    End Sub 
End Module

' This example of the explicit conversion from Single to Decimal

' Example of the explicit conversion from Double to Decimal.
Module DecimalFromDoubleDemo

    Const formatter As String = "{0,25:E16}{1,33}"
 
    ' Get the exception type name; remove the namespace prefix.
    Function GetExceptionType( ex As Exception ) As String

        Dim exceptionType   As String = ex.GetType( ).ToString( )
        Return exceptionType.Substring( _
            exceptionType.LastIndexOf( "."c ) + 1 )
    End Function

    ' Convert the Double argument; catch exceptions that are thrown.
    Sub DecimalFromDouble( argument As Double )

        Dim decValue    As Object
          
        ' Convert the Double argument to a Decimal value.
        Try
            decValue = Decimal.op_Explicit( argument )
        Catch ex As Exception
            decValue = GetExceptionType( ex )
        End Try

        ' Display the Decimal.
        Console.WriteLine( formatter, argument, decValue )
    End Sub 
       
    Sub Main( )

        Console.WriteLine( _
            "This example of the explicit conversion from Double " & _
            "to Decimal " & vbCrLf & "generates the following " & _
            "output." & vbCrLf )
        Console.WriteLine( formatter, "Double argument", _
            "Decimal value" )
        Console.WriteLine( formatter, "---------------", _
            "-------------" )
          
        ' Convert Double values and display the results.
        DecimalFromDouble( 1.234567890123E-30 )
        DecimalFromDouble( 1.2345678901234E-25 )
        DecimalFromDouble( 1.23456789012345E-20 )
        DecimalFromDouble( 1.234567890123456E-10 )
        DecimalFromDouble( 1.2345678901234567 )
        DecimalFromDouble( 1.23456789012345678E+12 )
        DecimalFromDouble( 1.234567890123456789E+28 ) 
        DecimalFromDouble( 1.234567890123456789E+30 )
    End Sub 
End Module

' This example of the explicit conversion from Double to Decimal

' Example of the explicit conversions from Decimal to Integer and 
' Decimal to UInteger.
Module DecimalToU_Int32Demo

    Const formatter As String = "{0,17}{1,19}{2,19}"

    ' Convert the decimal argument catch exceptions that are thrown.
    Public Sub DecimalToU_Int32(argument As Decimal)
        Dim Int32Value As Object
        Dim UInt32Value As Object

        ' Convert the argument to an int value.
        Try
            Int32Value = CInt(argument)
        Catch ex As Exception 
            Int32Value = ex.GetType().Name
        End Try

        ' Convert the argument to a uint value.
        Try
            UInt32Value = CUInt(argument)
        Catch ex As Exception
            UInt32Value = ex.GetType().Name
        End Try

        Console.WriteLine(formatter, argument, _
            Int32Value, UInt32Value)
    End Sub

    Public Sub Main( )
        Console.WriteLine( formatter, "Decimal Argument", _ 
            "Integer/Exception", "UInteger/Exception" )
        Console.WriteLine( formatter, "----------------", _ 
            "-------------", "--------------" )

        ' Convert decimal values and display the results.
        DecimalToU_Int32( 123d)
        DecimalToU_Int32(New Decimal(123000, 0, 0, False, 3))
        DecimalToU_Int32(123.999d)
        DecimalToU_Int32(4294967295.999d)
        DecimalToU_Int32(4294967296d)
        DecimalToU_Int32(2147483647.999d)
        DecimalToU_Int32(2147483648d)
        DecimalToU_Int32(-0.999d)
        DecimalToU_Int32(-1d)
        DecimalToU_Int32(-2147483648.999d)
        DecimalToU_Int32(-2147483649d)
    End Sub
End Module

' Example of the explicit conversions from Decimal to Short and 
' Decimal to UShort.
Module DecimalToU_Int16Demo

    Const formatter As String = "{0,16}{1,19}{2,19}"

    ' Convert the decimal argument and catch exceptions that are thrown.
    Public Sub DecimalToU_Int16(argument As Decimal)
        Dim Int16Value As Object
        Dim UInt16Value As Object

        ' Convert the argument to a Short value.
        Try
            Int16Value = CShort(argument)
        Catch ex As Exception 
            Int16Value = ex.GetType().Name
        End Try

        ' Convert the argument to a UShort value.
        Try
            UInt16Value = CUShort(argument)
        Catch ex As Exception
            UInt16Value = ex.GetType().Name
        End Try

        Console.WriteLine( formatter, argument, _
            Int16Value, UInt16Value )
    End Sub

    Public Sub Main( )
        Console.WriteLine( formatter, "Decimal argument", _ 
            "Short/Exception", "UShort/Exception" )
        Console.WriteLine( formatter, "----------------", _ 
            "---------------", "----------------" )

        ' Convert decimal values and display the results.
        DecimalToU_Int16(123d)
        DecimalToU_Int16(New Decimal( 123000, 0, 0, False, 3 ))
        DecimalToU_Int16(123.999d)
        DecimalToU_Int16(65535.999d)
        DecimalToU_Int16(65536d)
        DecimalToU_Int16(32767.999d)
        DecimalToU_Int16(32768d)
        DecimalToU_Int16(-0.999d)
        DecimalToU_Int16(-1d)
        DecimalToU_Int16(-32768.999d)
        DecimalToU_Int16(-32769d)
    End Sub
End Module
' This example displays the following output to the console:
'    Decimal argument    Short/Exception   UShort/Exception
'    ----------------    ---------------   ----------------
'                 123                123                123
'             123.000                123                123
'             123.999                124                124
'           65535.999  OverflowException  OverflowException
'               65536  OverflowException  OverflowException
'           32767.999  OverflowException              32768
'               32768  OverflowException              32768
'              -0.999                 -1  OverflowException
'                  -1                 -1  OverflowException
'          -32768.999  OverflowException  OverflowException
'              -32769  OverflowException  OverflowException

Module Example
    Public Sub Main( )
        ' Define an array of Decimal values.
        Dim values() As Decimal= { 0.0000000000000000000000000001d, 
                                   0.0000000000123456789123456789d,
                                   123d, 
                                   New Decimal(123000000, 0, 0, False, 6),
                                   123456789.123456789d, 
                                   123456789123456789123456789d, 
                                   Decimal.MinValue, Decimal.MaxValue }
        For Each value In values
            Dim dblValue As Single = CSng(value)
            Console.WriteLine("{0} ({1}) --> {2} ({3})", value,
                              value.GetType().Name, dblValue, 
                              dblValue.GetType().Name)
        Next
    End Sub
End Module

Option Strict On

Module Example
    Public Sub Main()
        ' Define an array of decimal values.
        Dim values() As Decimal = { 78d, New Decimal(78000, 0, 0, False, 3),
                                    78.999d, 255.999d, 256d, 127.999d,
                                    128d, -0.999d, -1d, -128.999d, 
                                    -129d }           
        For Each value In values
           Try
              Dim byteValue As SByte = CSByte(value)
              Console.WriteLine("{0} ({1}) --> {2} ({3})", value,
                                value.GetType().Name, byteValue, 
                                byteValue.GetType().Name)
           Catch e As OverflowException
              Console.WriteLine("OverflowException: Cannot convert {0}",
                                value)
           End Try
        Next   
    End Sub
End Module

' Example of the explicit conversions from Decimal to Long and 
' Decimal to ULong.
Module DecimalToU_Int64Demo

    Const formatter As String = "{0,25}{1,22}{2,22}"

    ' Convert the decimal argument catch exceptions that are thrown.
    Public Sub DecimalToU_Int64(argument As Decimal)
        Dim Int64Value As Object
        Dim UInt64Value As Object

        ' Convert the argument to a long value.
        Try
            Int64Value = CLng(argument)
        Catch ex As Exception
            Int64Value = ex.GetType().Name
        End Try

        ' Convert the argument to a ulong value.
        Try
            UInt64Value = CULng(argument)
        Catch ex As Exception
            UInt64Value = ex.GetType().Name
        End Try

        Console.WriteLine(formatter, argument, _ 
            Int64Value, UInt64Value)
    End Sub

    Public Sub Main( )
        Console.WriteLine( formatter, "Decimal argument", _
            "Long/Exception", "ULong/Exception" )
        Console.WriteLine( formatter, "----------------", _
            "--------------", "---------------" )

        ' Convert decimal values and display the results.
        DecimalToU_Int64(123d)
        DecimalToU_Int64(New Decimal(123000, 0, 0, False, 3))
        DecimalToU_Int64(123.999d)
        DecimalToU_Int64(18446744073709551615.999d)
        DecimalToU_Int64(18446744073709551616d)
        DecimalToU_Int64(9223372036854775807.999d)
        DecimalToU_Int64(9223372036854775808d)
        DecimalToU_Int64(-0.999d)
        DecimalToU_Int64(-1d)
        DecimalToU_Int64(-9223372036854775808.999d)
        DecimalToU_Int64(-9223372036854775809d)
    End Sub
End Module

Module Example
    Public Sub Main( )
        ' Define an array of Decimal values.
        Dim values() As Decimal= { 0.0000000000000000000000000001d, 
                                   0.0000000000123456789123456789d,
                                   123d, 
                                   New Decimal(123000000, 0, 0, False, 6),
                                   123456789.123456789d, 
                                   123456789123456789123456789d, 
                                   Decimal.MinValue, Decimal.MaxValue }
        For Each value In values
            Dim dblValue As Double = CDbl(value)
            Console.WriteLine("{0} ({1}) --> {2} ({3})", value,
                              value.GetType().Name, dblValue, 
                              dblValue.GetType().Name)
        Next
    End Sub
End Module

Option Strict On

Module Example
    Public Sub Main()
        ' Define an array of decimal values.
        Dim values() As Decimal = { 78d, New Decimal(78000, 0, 0, False, 3),
                                    78.999d, 255.999d, 256d, 127.999d,
                                    128d, -0.999d, -1d, -128.999d, 
                                    -129d }           
        For Each value In values
           Try
              Dim byteValue As Byte = CByte(value)
              Console.WriteLine("{0} ({1}) --> {2} ({3})", value,
                                value.GetType().Name, byteValue, 
                                byteValue.GetType().Name)
           Catch e As OverflowException
              Console.WriteLine("OverflowException: Cannot convert {0}",
                                value)
           End Try
        Next   
    End Sub
End Module