Numeric value

Question

How to know whether a TextBox.Text Value is a number? I mean, how to know if TextBox is having '1234' or is having 'ABCD'? May be is easy, but I'm a begginer. Sorry. Thanx in advance.

ZonghanHo_apol-mp · Answer

test

Carlos Sanchez · Answer

I think I need to read more about System.Globalization Thank you.

kovan · Answer

http://www.publicjoe.f9.co.uk/csharp/code/simcon/snip038a.cs something i wrote long time ago

Carlos Sanchez · Answer

yeah, is another solution similar. Thanx.

Adam Erstelle · Answer

Another solution would be to try to parse the string value into a double value. Catch an exception, and if there is an exception (because parsing "ABC" into a double value will throw an exception), you can handle it appropriately, and display any message to the user. Just another option

Carlos Sanchez · Answer

That was usefull. Thanks Peter T Jones.

p.jones · Answer

You create a String object from TextBox.Text.toString. You iterate on String's characters using method/property Chars. For each Char object returned used the IsDigit method to check whether this is a digit. There are other available checks on the value class of a Char. For detail, see visual studio > help > search> "String Members" and "Char Members". I think there may be a higher level check on the TextBox.text property to check if uit is a numeric value but that allows fractional numbers currency signs etc.

Numeric value

Answers (7)