اقرأ باللغة الإنجليزية تحرير

مشاركة عبر


StreamWriter.Null Field

Definition

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Provides a StreamWriter with no backing store that can be written to, but not read from.

public: static initonly System::IO::StreamWriter ^ Null;
public static readonly System.IO.StreamWriter Null;
 staticval mutable Null : System.IO.StreamWriter
Public Shared ReadOnly Null As StreamWriter 

Field Value

Examples

The following example demonstrates a use of the Null field.

if ( sw->Equals( StreamWriter::Null ) )
{
   sw->WriteLine( "The store can be written to, but not read from." );
}
if(sw.Equals(StreamWriter.Null))
{
    sw.WriteLine("The store can be written to, but not read from.");
}
If Sw.Equals(StreamWriter.Null) Then
    Sw.WriteLine("The store can be written to, but not read from.")
End If

Remarks

Use Null to redirect output to a StreamWriter that will not consume any operating system resources.

When the StreamWriter.Write methods are invoked on Null, the call simply returns, and no data is actually written to any backing store.

For a list of common I/O tasks, see Common I/O Tasks.

Applies to

منتج الإصدارات
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 2.0, 2.1
UWP 10.0

See also