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c#stringfindexact-match

C# find exact-match in string

How can I search for an exact match in a string? For example, If I had a string with this text:

label
label:
labels

And I search for label, I only want to get the first match, not the other two. I tried the Contains and IndexOf method, but they also give me the 2nd and 3rd matches.

Solution

  • You can use a regular expression like this:

    bool contains = Regex.IsMatch("Hello1 Hello2", @"(^|\s)Hello(\s|$)"); // yields false
bool contains = Regex.IsMatch("Hello1 Hello", @"(^|\s)Hello(\s|$)"); // yields true

    The \b is a word boundary check, and used like above it will be able to match whole words only.

    I think the regex version should be faster than Linq.

    Reference