How do you check if a string contains an int at a specific location?

Question

I want to make sure that a folder has the correct name format before proceeding. The code below demonstrates what I am trying to do, although {char.IsDigit} doesn't work. I would like to replace char.IsDigit with something that means "any digit".

if(versionName == $"Release {char.IsDigit}.{char.IsDigit}.{char.IsDigit}.{char.IsDigit}")
{
    //Do something
}

Thanks

Answer 1

You want to use Regex.IsMatch with a regex like:

if(Regex.IsMatch(versionName, @"^Release \d\.\d\.\d\.\d$"))
{
    //Do something
}

Note \\d just matches a single digit, if there can be more than 1 digits

@"^Release \d+\.\d+\.\d+\.\d+$"

And tightening it all up:

@"^Release \d+(?:\.\d+){3}$"

See the regex demo and its graph :