long.Parse() C#

Question

How would I convert a string, say "-100,100", to long in C#.

I currently have a line of code which is

long xi = long.Parse(x, System.Globalization.NumberStyles.AllowThousands);

but this breaks when x is "a negative number".

My approach:

long xi = long.Parse("-100,253,1", 
System.Globalization.NumberStyles.AllowLeadingSign & System.Globalization.NumberStyles.AllowThousands);

was wrong, as it broke.

Solution 1

give this a go:

long xi = long.Parse(x, System.Globalization.NumberStyles.AllowThousands | System.Globalization.NumberStyles.AllowLeadingSign);

It may well be because you are declaring flags you may need to declair all possible flags that will be hit. I've just confirmed this code as working in a test project using your given string value in the question. Let me know if it meets your requirements. When declaring multiple flags in a single parameter use | instead of &

edit: http://msdn.microsoft.com/en-us/library/cc138362.aspx Find an explination of the different bitwise operators under the "Enumeration Types as Bit Flags" heading (That was harder to find than i thought.)

Solution 2

I would use TryParse instead of Parse, in order to avoid exceptions, i.e.:

long xi;
if (long.TryParse(numberString, System.Globalization.NumberStyles.AllowThousands | System.Globalization.NumberStyles.AllowLeadingSign, null, out xi))
    {
        // OK, use xi
    }
    else
    {
        // not valid string, xi is 0
    }

Comments

[Skintkingle]

Slight typo on your "Parse" should be "TryParse", otherwise better answer. Shame I didnt feel the need to point out TryParse to him.