Check if Windows batch variable starts with a specific string

Question

How can I find out (with Windows a batch command), if, for example, a variable starts with ABC?

I know that I can search for variables if I know the whole content (if "%variable%"=="abc"), but I want that it only looks after the beginning.

I also need it to find out where the batch file is located, so if there is a other command that reveals the file's location, please let me know.

Solution 1

Use the variable substring syntax:

IF "%variable:~0,3%"=="ABC" [...]

If you need the path to the batch file without the batch file name, you can use the variable:

%~dp0

Syntax for this is explained in the help for the for command, although this variable syntax extends beyond just the for command syntax.

Solution 2

to find batch file location use %0 (gives full patch to current batch file) or %CD% variable which gives local directory

Comments

[Admin]

And 0,3% means it searches for the first 3 letters?

[jeb]

No, it gets the first three characters from the variable. Then the first characters are compared with "abc"

[Bacon Bits]

@EricRösch It's a substring. It means "Starting with character 0 (the first) give me 3 characters".

[Admin]

Thank you, that's what I wanted to know.

[kxr]

Is it possible directly on %1 without set variable=%1? echo "%1:~0,2" echo "%1:~0,2%" echo "%%1:~0,2%" echo "%%1:~0,2%%" echo "%%%1:~0,2%" echo "%%%1:~0,2%%" echo "%%%%1:~0,2%" : they all don't work.

[Bacon Bits]

@kxr Not as far as I'm aware. Argument variables don't appear to support substrings, although I believe they do support search and replace.

[Jesse Chisholm]

And %~dp0 gives just the drive and path, without the filename of the current batch file.

[vikyd]

But sometimes I don't know the length