TextInfo.ReadOnly(TextInfo) Método

Definición

Espacio de nombres:

System.Globalization

Ensamblado:

System.Runtime.dll

Source:

TextInfo.cs

Devuelve una versión de solo lectura del objeto TextInfo especificado.

public:
 static System::Globalization::TextInfo ^ ReadOnly(System::Globalization::TextInfo ^ textInfo);

public static System.Globalization.TextInfo ReadOnly (System.Globalization.TextInfo textInfo);

static member ReadOnly : System.Globalization.TextInfo -> System.Globalization.TextInfo

Public Shared Function ReadOnly (textInfo As TextInfo) As TextInfo

Parámetros

textInfo

TextInfo

Un objeto TextInfo.

Devoluciones

TextInfo

Objeto TextInfo especificado por el parámetro textInfo, si textInfo es de solo lectura.

o bien

Clon miembro a miembro de solo lectura del objeto TextInfo especificado por textInfo, si textInfo no es de solo lectura.

Excepciones

ArgumentNullException

textInfo es null.

Ejemplos

En el ejemplo de código siguiente se muestran los Clone métodos y ReadOnly .

// This example demonstrates the TextInfo.Clone() and
// TextInfo.ReadOnly() methods.

using System;
using System.Globalization;

class Sample
{
    public static void Main()
    {
// Get the TextInfo of a predefined culture that ships with
// the .NET Framework.
    CultureInfo ci = new CultureInfo("en-US");
    TextInfo ti1 = ci.TextInfo;

// Display whether the TextInfo is read-only or not.
    DisplayReadOnly("1) The original TextInfo object", ti1);
    Console.WriteLine();

// Create a clone of the original TextInfo and cast the clone to a TextInfo type.
    Console.WriteLine("2a) Create a clone of the original TextInfo object...");
    TextInfo ti2 = (TextInfo)ti1.Clone();

// Display whether the clone is read-only.
    DisplayReadOnly("2b) The TextInfo clone", ti2);

// Set the ListSeparator property on the TextInfo clone.
    Console.WriteLine("2c) The original value of the clone's ListSeparator " +
                      "property is \"{0}\".", ti2.ListSeparator);
    ti2.ListSeparator = "/";
    Console.WriteLine("2d) The new value of the clone's ListSeparator " +
                      "property is \"{0}\".\n", ti2.ListSeparator);

// Create a read-only clone of the original TextInfo.
    Console.WriteLine("3a) Create a read-only clone of the original TextInfo object...");
    TextInfo ti3 = TextInfo.ReadOnly(ti1);

// Display whether the read-only clone is actually read-only.
    DisplayReadOnly("3b) The TextInfo clone", ti3);

// Try to set the ListSeparator property of a read-only TextInfo object. Use the
// IsReadOnly property again to determine whether to attempt the set operation. You
// could use a try-catch block instead and catch an InvalidOperationException when
// the set operation fails, but that programming technique is inefficient.
    Console.WriteLine("3c) Try to set the read-only clone's LineSeparator " +
                      "property.");
    if (ti3.IsReadOnly == true)
        {
        Console.WriteLine("3d) The set operation is invalid.");
        }
    else
        {
        // This clause is not executed.
        ti3.ListSeparator = "/";
        Console.WriteLine("3d) The new value of the clone's ListSeparator " +
                          "property is \"{0}\".\n", ti2.ListSeparator);
        }
    }

    private static void DisplayReadOnly(string caption, TextInfo ti)
    {
    Console.WriteLine("{0} is {1}read-only.",
                      caption, ti.IsReadOnly ? "" : "not ");
    }
}

/*
This code example produces the following results:

1) The original TextInfo object is not read-only.

2a) Create a clone of the original TextInfo object...
2b) The TextInfo clone is not read-only.
2c) The original value of the clone's ListSeparator property is ",".
2d) The new value of the clone's ListSeparator property is "/".

3a) Create a read-only clone of the original TextInfo object...
3b) The TextInfo clone is read-only.
3c) Try to set the read-only clone's LineSeparator property.
3d) The set operation is invalid.

*/

' This example demonstrates the TextInfo.Clone() and
' TextInfo.ReadOnly() methods.

Imports System.Globalization

Class Sample
    Public Shared Sub Main() 
        ' Get the TextInfo of a predefined culture that ships with 
        ' the .NET Framework.
        Dim ci As New CultureInfo("en-US")
        Dim ti1 As TextInfo = ci.TextInfo
        
        ' Display whether the TextInfo is read-only or not.
        DisplayReadOnly("1) The original TextInfo object", ti1)
        Console.WriteLine()
        
        ' Create a clone of the original TextInfo and cast the clone to a TextInfo type.
        Console.WriteLine("2a) Create a clone of the original TextInfo object...")
        Dim ti2 As TextInfo = CType(ti1.Clone(), TextInfo)
        
        ' Display whether the clone is read-only.
        DisplayReadOnly("2b) The TextInfo clone", ti2)
        
        ' Set the ListSeparator property on the TextInfo clone.
        Console.WriteLine("2c) The original value of the clone's ListSeparator " & _
                          "property is ""{0}"".", ti2.ListSeparator)
        ti2.ListSeparator = "/"
        Console.WriteLine("2d) The new value of the clone's ListSeparator " & _ 
                          "property is ""{0}""." & vbCrLf, ti2.ListSeparator)
        
        ' Create a read-only clone of the original TextInfo.
        Console.WriteLine("3a) Create a read-only clone of the original TextInfo object...")
        Dim ti3 As TextInfo = TextInfo.ReadOnly(ti1)
        
        ' Display whether the read-only clone is actually read-only.
        DisplayReadOnly("3b) The TextInfo clone", ti3)
        
        ' Try to set the ListSeparator property of a read-only TextInfo object. Use the
        ' IsReadOnly property again to determine whether to attempt the set operation. You 
        ' could use a try-catch block instead and catch an InvalidOperationException when
        ' the set operation fails, but that programming technique is inefficient.
        Console.WriteLine("3c) Try to set the read-only clone's LineSeparator property.")
        If ti3.IsReadOnly = True Then
            Console.WriteLine("3d) The set operation is invalid.")
        Else
            ' This clause is not executed.
            ti3.ListSeparator = "/"
            Console.WriteLine("3d) The new value of the clone's ListSeparator " & _ 
                              "property is ""{0}""." & vbCrLf, ti2.ListSeparator)
        End If
    
    End Sub
    
    Private Shared Sub DisplayReadOnly(ByVal caption As String, ByVal ti As TextInfo)
        Dim middle As String
        If ti.IsReadOnly = True Then
            middle = ""
        Else 
            middle = "not "
        End If        
        Console.WriteLine("{0} is {1}read-only.", caption, middle)
    End Sub
End Class

'
'This code example produces the following results:
'
'1) The original TextInfo object is not read-only.
'
'2a) Create a clone of the original TextInfo object...
'2b) The TextInfo clone is not read-only.
'2c) The original value of the clone's ListSeparator property is ",".
'2d) The new value of the clone's ListSeparator property is "/".
'
'3a) Create a read-only clone of the original TextInfo object...
'3b) The TextInfo clone is read-only.
'3c) Try to set the read-only clone's LineSeparator property.
'3d) The set operation is invalid.
'

Consulte también

• MemberwiseClone()