Reading and Writing in files: Difference between revisions

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The variables we use to read/write can only hold up to 1024 bytes, but this is harldy a problem.
The variables we use to read/write can only hold up to 1024 bytes, but this is harldy a problem.
Notice that every example used a different mode to open the file "w" "a" and "r".
Notice that every example used a different mode to open the file "w" "a" and "r".
[[{{ns:14}}:Code Examples]]

Revision as of 21:28, 30 April 2005

Author: n0On3 (talk, contrib)


Description

This example is to show you how easy is to read/write in files.

Usage 1

This will overwrite SomeFile.txt contents or create it and put "hello" inside:

FileOpen $4 "$DESKTOP\SomeFile.txt" w
FileWrite $4 "hello"
FileClose $4

Usage 2

If the file exists and you don't want to lose its contents us this:

FileOpen $4 "$DESKTOP\SomeFile.txt" a
FileSeek $4 0 END
FileWrite $4 "$\r$\n" ; we write a new line
FileWrite $4 "hello"
FileWrite $4 "$\r$\n" ; we write an extra line
FileClose $4 ; and close the file

That "$\r$\n" means "carriage return + new line". This is how windows knows that there's a new line in the file.

Usage 3

For reading files:

FileOpen $4 "$DESKTOP\SomeFile.txt" r
FileSeek $4 1000 ; we want to start reading at the 1000th byte
FileRead $4 $1 ; we read until the end of line (including carriage return and new line) and save it to $1
FileRead $4 $2 10 ; read 10 characters from the next line
FileClose $4 ; and close the file

The variables we use to read/write can only hold up to 1024 bytes, but this is harldy a problem. Notice that every example used a different mode to open the file "w" "a" and "r".