How to resolve Buffer overflow while reading large text files over 2GB?

I am trying to read a large text file in JScript to search for a string, but encountering overflow exception. I wrote the following code.

var ForReading = 1;
var TriStateFalse = 0;
var strFileData;

var fso, objFile, objTS;
fso = new ActiveXObject("Scripting.FileSystemObject");
objFile = fso.GetFile("Sample2GBFile");

strFileData = objTS.Read(objFile.Size);
if(strFileData .indexOf("String to search") > 0 )
{
wShShell.Echo("Found...");
} 

In the above code, I am getting the buffer overflow as the 2GB file is unab开发者_如何学运维le to fit into the buffer. pls help how to resolve this.

Read smaller portions of the file, check for string, empty buffer, read more. Just make sure you account for the length of the string when reading a chunk so as to prevent cutting it and thus missing a hit.

Loop over a line instead of reading the whole file

http://techsupt.winbatch.com/ts/T000001033F64.html

:test4
; read single chars from a line, count chars.
testfile = "d:\temp\test.ascii.txt"
MyFile = fso.OpenTextFile(testfile, ForReading)       ; Open a file as a TextStream
ThisLine = ""
While !MyFile.AtEndOfLine                             ; Is the current position at the end of a line? 
   ThisColumnCount = MyFile.Column                    ; Current column number.
   ThisLine        = StrCat(ThisLine, MyFile.Read(1)) ; Read a specific number of characters into a string.
   NextColumnCount = MyFile.Column                    ; Current column number.
EndWhile
MyFile.Close                                          ; Close a text stream.
ObjectClose(MyFile)

:test5
; read lines, count lines.
testfile = "d:\temp\test.ascii.txt"
MyFile = fso.OpenTextFile(testfile, ForReading)       ; Open a file as a TextStream
While !MyFile.AtEndOfStream                           ; Is the current position at the end of the stream?
   ThisLineCount = MyFile.Line                        ; Current line number.
   ThisLine      = MyFile.ReadLine                    ; Read an entire line into a string.
   NextLineCount = MyFile.Line                        ; Current line number.
EndWhile
MyFile.Close                                          ; Close a text stream.
ObjectClose(MyFile)