Regex match first characters of string

I am trying to create a regex that will match the first 3 characters of a string,

If I have a string ABCFFFF I want to verify that th开发者_如何学Goe first 3 characters are ABC.

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It's pretty straightforward, the pattern would be ^ABC

As others may point out, using regular expressions for such a task is an overkill. Any programming language with regex support can do it better with simple string manipulations.

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Just simple regex will work:

/^ABC/

But is it a good use case for using regex, I am not sure. Consider using substring in whatever language/platform you're using.

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"^ABC" should work. '^' matches the start in most regex implementations.