Microsoft® Scripting Library - FileSystemObject Working with Files |
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There are two major categories of file manipulation:
- Creating, adding, or removing data, and reading files
- Moving, copying, and deleting files
There are three ways to create an empty text file (sometimes referred to as a "text stream").The first way is to use the CreateTextFile method. The following example demonstrates how to create a text file using this method in VBScript:
To use this method in JScript, use this code:Dim fso, f1 Set fso = CreateObject("Scripting.FileSystemObject") Set f1 = fso.CreateTextFile("c:\testfile.txt", True)
View this sample code to see how the CreateTextFile method is used in FileSystemObject.var fso, f1; fso = new ActiveXObject("Scripting.FileSystemObject"); f1 = fso.CreateTextFile("c:\\testfile.txt", true);The second way to create a text file is to use the OpenTextFile method of the FileSystemObject object with the ForWriting flag set. In VBScript, the code looks like this example:
To create a text file using this method in JScript, use this code:Dim fso, ts Const ForWriting = 2 Set fso = CreateObject("Scripting. FileSystemObject") Set ts = fso.OpenTextFile("c:\test.txt", ForWriting, True)
A third way to create a text file is to use the OpenAsTextStream method with the ForWriting flag set. For this method, use the following code in VBScript:var fso, ts; var ForWriting= 2; fso = new ActiveXObject("Scripting.FileSystemObject"); ts = fso.OpenTextFile("c:\\test.txt", ForWriting, true);
In JScript, use the code in the following example:Dim fso, f1, ts Const ForWriting = 2 Set fso = CreateObject("Scripting.FileSystemObject") fso.CreateTextFile ("c:\test1.txt") Set f1 = fso.GetFile("c:\test1.txt") Set ts = f1.OpenAsTextStream(ForWriting, True)
var fso, f1, ts; var ForWriting = 2; fso = new ActiveXObject("Scripting.FileSystemObject"); fso.CreateTextFile ("c:\\test1.txt"); f1 = fso.GetFile("c:\\test1.txt"); ts = f1.OpenAsTextStream(ForWriting, true);
Once the text file is created, add data to the file using the following three steps:
To open an existing file, use either the OpenTextFile method of the FileSystemObject object or the OpenAsTextStream method of the File object.
- Open the text file.
- Write the data.
- Close the file.
To write data to the open text file, use the Write, WriteLine, or WriteBlankLines methods of the TextStream object, according to the tasks outlined in the following table.
Task Method Write data to an open text file without a trailing newline character. Write Write data to an open text file with a trailing newline character. WriteLine Write one or more blank lines to an open text file. WriteBlankLines View this sample code to see how the Write, WriteLine, and WriteBlankLines methods are used in FileSystemObject.
To close an open file, use the Close method of the TextStream object.
View this sample code to see how the Close method is used in FileSystemObject.
Note The newline character contains a character or characters (depending on the operating system) to advance the cursor to the beginning of the next line (carriage return/line feed). Be aware that the end of some strings may already have such nonprinting characters. The following VBScript example demonstrates how to open a file, use all three write methods to add data to the file, and then close the file:
This example demonstrates how to use the three methods in JScript:Sub CreateFile() Dim fso, tf Set fso = CreateObject("Scripting.FileSystemObject") Set tf = fso.CreateTextFile("c:\testfile.txt", True) ' Write a line with a newline character. tf.WriteLine("Testing 1, 2, 3.") ' Write three newline characters to the file. tf.WriteBlankLines(3) ' Write a line. tf.Write ("This is a test.") tf.Close End Sub
function CreateFile() { var fso, tf; fso = new ActiveXObject("Scripting.FileSystemObject"); tf = fso.CreateTextFile("c:\\testfile.txt", true); // Write a line with a newline character. tf.WriteLine("Testing 1, 2, 3.") ; // Write three newline characters to the file. tf.WriteBlankLines(3) ; // Write a line. tf.Write ("This is a test."); tf.Close(); }
To read data from a text file, use the Read, ReadLine, or ReadAll method of the TextStream object. The following table describes which method to use for various tasks.
Task Method Read a specified number of characters from a file. Read Read an entire line (up to, but not including, the newline character). ReadLine Read the entire contents of a text file. ReadAll View this sample code to see how the ReadAll and ReadLine methods are used in FileSystemObject.
If you use the Read or ReadLine method and want to skip to a particular portion of data, use the Skip or SkipLine method. The resulting text of the read methods is stored in a string which can be displayed in a control, parsed by string functions (such as Left, Right, and Mid), concatenated, and so forth.
The following VBScript example demonstrates how to open a file, write to it, and then read from it:
This code demonstrates the same thing in JScript:Sub ReadFiles Dim fso, f1, ts, s Const ForReading = 1 Set fso = CreateObject("Scripting.FileSystemObject") Set f1 = fso.CreateTextFile("c:\testfile.txt", True) ' Write a line. Response.Write "Writing file <br>" f1.WriteLine "Hello World" f1.WriteBlankLines(1) f1.Close ' Read the contents of the file. Response.Write "Reading file <br>" Set ts = fso.OpenTextFile("c:\testfile.txt", ForReading) s = ts.ReadLine Response.Write "File contents = '" & s & "'" ts.Close End Sub
function ReadFiles() { var fso, f1, ts, s; var ForReading = 1; fso = new ActiveXObject("Scripting.FileSystemObject"); f1 = fso.CreateTextFile("c:\\testfile.txt", true); // Write a line. Response.Write("Writing file <br>"); f1.WriteLine("Hello World"); f1.WriteBlankLines(1); f1.Close(); // Read the contents of the file. Response.Write("Reading file <br>"); ts = fso.OpenTextFile("c:\\testfile.txt", ForReading); s = ts.ReadLine(); Response.Write("File contents = '" + s + "'"); ts.Close(); }
The FSO object model has two methods each for moving, copying, and deleting files, as described in the following table.
Task Method Move a file File.Move or FileSystemObject.MoveFile Copy a file File.Copy or FileSystemObject.CopyFile Delete a file File.Delete or FileSystemObject.DeleteFile View this sample code to see two ways to delete a file in FileSystemObject.
The following VBScript example creates a text file in the root directory of drive C, writes some information to it, moves it to a directory called \tmp, makes a copy of it in a directory called \temp, then deletes the copies from both directories.
To run the following example, create directories named \tmp and \temp in the root directory of drive C:
This code shows the same thing in JScript:Sub ManipFiles Dim fso, f1, f2, s Set fso = CreateObject("Scripting.FileSystemObject") Set f1 = fso.CreateTextFile("c:\testfile.txt", True) Response.Write "Writing file <br>" ' Write a line. f1.Write ("This is a test.") ' Close the file to writing. f1.Close Response.Write "Moving file to c:\tmp <br>" ' Get a handle to the file in root of C:\. Set f2 = fso.GetFile("c:\testfile.txt") ' Move the file to \tmp directory. f2.Move ("c:\tmp\testfile.txt") Response.Write "Copying file to c:\temp <br>" ' Copy the file to \temp. f2.Copy ("c:\temp\testfile.txt") Response.Write "Deleting files <br>" ' Get handles to files' current location. Set f2 = fso.GetFile("c:\tmp\testfile.txt") Set f3 = fso.GetFile("c:\temp\testfile.txt") ' Delete the files. f2.Delete f3.Delete Response.Write "All done!" End Sub
function ManipFiles() { var fso, f1, f2, s; fso = new ActiveXObject("Scripting.FileSystemObject"); f1 = fso.CreateTextFile("c:\\testfile.txt", true); Response.Write("Writing file <br>"); // Write a line. f1.Write("This is a test."); // Close the file to writing. f1.Close(); Response.Write("Moving file to c:\\tmp <br>"); // Get a handle to the file in root of C:\. f2 = fso.GetFile("c:\\testfile.txt"); // Move the file to \tmp directory. f2.Move ("c:\\tmp\\testfile.txt"); Response.Write("Copying file to c:\\temp <br>"); // Copy the file to \temp. f2.Copy ("c:\\temp\\testfile.txt"); Response.Write("Deleting files <br>"); // Get handles to files' current location. f2 = fso.GetFile("c:\\tmp\\testfile.txt"); f3 = fso.GetFile("c:\\temp\\testfile.txt"); // Delete the files. f2.Delete(); f3.Delete(); Response.Write("All done!"); }