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Microsoft® JScript™
OpenAsTextStream Method
 Language Reference 
 Version 3 

See Also                  Applies To

Opens a specified file and returns a TextStream object that can be used to read from, write to, or append to the file.
object.OpenAsTextStream([iomode, [format]])

The OpenAsTextStream method syntax has these parts:

Part Description
object Required. Always the name of a File object.
iomode Optional. Indicates input/output mode. Can be one of three constants: ForReading, ForWriting, or ForAppending.
format Optional. One of three Tristate values used to indicate the format of the opened file. If omitted, the file is opened as ASCII.

The iomode argument can have any of the following settings:

Constant Value Description
ForReading 1 Open a file for reading only. You can't write to this file.
ForWriting 2 Open a file for writing. If a file with the same name exists, its previous contents are overwritten.
ForAppending 8 Open a file and write to the end of the file.

The format argument can have any of the following settings:

Constant Value Description
TristateUseDefault -2 Opens the file using the system default.
TristateTrue -1 Opens the file as Unicode.
TristateFalse  0 Opens the file as ASCII.

The OpenAsTextStream method provides the same functionality as the OpenTextFile method of the FileSystemObject. In addition, the OpenAsTextStream method can be used to write to a file.

The following code illustrates the use of the OpenAsTextStream method:

function TextStreamTest( )
    var ForReading = 1, ForWriting = 2, ForAppending = 3;
    var TristateUseDefault = -2, TristateTrue = -1, TristateFalse = 0;
    var fs, f, ts, s;
    fs = new ActiveXObject("Scripting.FileSystemObject");
    fs.CreateTextFile( "test1.txt" );           // Create a file
    f = fs.GetFile("test1.txt");
    ts = f.OpenAsTextStream(ForWriting, TristateUseDefault);
    ts.Write( "Hello World" );
    ts.Close( );
    ts = f.OpenAsTextStream(ForReading, TristateUseDefault);
    s = ts.ReadLine( );
    ts.Close( );

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