What's a C# regular expression that'll validate currency, float or integer?

Question

What is a regular expression suitable for C# that\'ll validate a number if it matches the following?

 $1,000,000.150
 $10000000.199
 $10000 
 1,         


        

Answer 1

^\$?(\d{1,3},?(\d{3},?)*\d{3}(\.\d{1,3})?|\d{1,3}(\.\d{2})?)$

Answer 2

I think I've found a problem with ssg's solution (or perhaps an MS bug!).

Running this:

float.TryParse("0,2",NumberStyles.Currency, CultureInfo.GetCultureInfo("en-US"), out num)

Returns true. Surely "0,2" isn't a valid currency value?

Answer 3

This regular Expression works for me:

'^[$]{0,1}([0-9]+[,]?[0-9]+|[0-9]{1,3}([.][0-9]{3})*([,][0-9]+)?)$'

with switch

'^\${0,1}(\d+,?[0-9]+|\d{1,3}(\.\d{3})*(,\d+)?)$'

it works for

• $1,000,000.150
• 10000000.199
• $10000
• 1,000,000.150
• 100000.123
• 10000

Answer 4

Be careful with floats. Eventually you will hit a case such as 0.01 represented as 0.00999999. Strings or integers are better to use.

Answer 5

You can use csmba's regex if you make one slight modification to it.

^\$?(\d{1,3},?(\d{3},?)*\d{3}(.\d{0,3})?|\d{1,3}(.\d{2})?)$

Answer 6

Use this regular expression for US currency \$(\d)*\d Matches $300,$12900 Non-Match $12900.00