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Can we use regular expression to match numbers not preceded by a specified set of characters

Posted By:      Posted Date: May 22, 2011    Points: 0   Category :WPF

I have been trying to come up with a RegEx that would match numbers (including decimals and negative numbers) that are not preceded by a specified set of characters. For example:

Specified set of characters (not including comma): c, t

Input string: “This c2 is one element. And t-4a, d25, c2.54, v4.28, q58 are other elements”

Desired result (the numbers not preceded by c and t):

The pattern I tried: [^ct](-?\d+\.?\d*|\.\d+)

The matches I got (Note: I fetched the results from Group 1):


I don’t want the numbers in bold to be returned since in t-4a the integer -4 is preceded by t, and in c2.54, 2.54 is preceded by c.

Can we refine the above pattern or is it even possible?

Thank you.

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