Why double.TryParse("0.0000", out doubleValue) returns false ?

Question

I am trying to parse string "0.0000" with double.TryParse() but I have no idea why would it return false in this particular example. When I pass integer-like strings e.g. "5" it parses correctly to value of 5 .

Any ideas why it is happening ?

Answer 1

it takes the localization settings at runtime into account... perhaps you are running this on a system where . is not the decimal point but , instead...

In your specific case I assume you want a fixed culture regardless of the system you are running on with . as the decimal point:

double.TryParse("0.0000", NumberStyles.Number, CultureInfo.CreateSpecificCulture ("en-US"), out temp) 

OR

double.TryParse("0.0000", NumberStyles.Number,CultureInfo.InvariantCulture, out temp) 

Some MSDN reference links:

• Double.TryParse(String, NumberStyles, IFormatProvider, Double)
• CultureInfo.CreateSpecificCulture(String)
• IFormatProvider Interface
• CultureInfo.InvariantCulture Property

Answer 2

TryParse uses the current culture by default. And if your current culture uses a decimal seperator different from ., it can't parse 0.0000 as you intend. So you need to pass in CultureInfo.InvariantCulture.

var numberStyle = NumberStyles.AllowLeadingWhite |                  NumberStyles.AllowTrailingWhite |                  NumberStyles.AllowLeadingSign |                  NumberStyles.AllowDecimalPoint |                  NumberStyles.AllowThousands |                  NumberStyles.AllowExponent;//Choose what you need double.TryParse( "0.0000", numberStyle, CultureInfo.InvariantCulture, out myVar)