regex allow only numbers or empty string

Question

Can someone help me create this regex. I need it to check to see if the string is either entirely whitespace(empty) or if it only contains positive whole numbers. If anything el

Answer 1

^\d+([\.\,][0]{2})?$

I found this worked for me. Allow any whole number, but only a decimal of .00

Pass

• 999 90
• 100
• 100.00
• 101.00
• 1000.00

Fails

• 101.01
• 1000.99

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