parsing a string value to double with comma decimal seperator

if there is any one who find a solution to this

string x = "7,50";
string y = "5";
double a = double.Parse(x);
double b = double.Parse(y);
double c = a - b;

then the result must be 2,50.

but I got 70. because of decimal point x is treated as 75.

Just specify the appropriate culture to double.Parse. For example:

CultureInfo french = new CultureInfo("fr-FR");
double x = double.Parse("7,50", french);

I suspect you actually had "7,5" as a value, however - as "7,50" would be parsed as "750" if you were using a culture which didn't use comma as the separator.

Of course, if these are currency values you should consider using decimal instead of double to start with...

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