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c#regexregex-group

Regular expression that stops at first letter encountered

I want my regex expression to stop matching numbers of length between 2 and 10 after it encounters a letter.

So far I've come up with (\d{2,10})(?![a-zA-Z]) this. But it continues to match even after letters are encountered. 2216101225 /ROC/PL FCT DIN 24.03.2022 PL ERBICIDE' - this is the text I've been testing the regex on, but it matches 24 03 and 2022 also. This is tested and intended for C#.

Can you help ? Thanks

Solution

  • You can use the following .NET regex

    (?<=^\P{L}*)(?<!\d)\d{2,10}(?!\d)
(?<=^[^a-zA-Z]*)(?<!\d)\d{2,10}(?!\d)

    See the regex demo. Details:

    • (?<=^\P{L}*) - there must be no letters from the current position till the start of string ((?<=^[^a-zA-Z]*) only supports ASCII letters)
    • (?<!\d) - no digit immediately on the left is allowed.
    • \d{2,10} - two to ten digits
    • (?!\d) - no digit immediately on the right is allowed.