Why does TimeSpan string formatting resolve into an Exception?

Question

I have the following line of code in my c# MVC2 Project:

string.Format(@"{0\:HH\:mm}", new TimeSpan(0))

This line is resulting in the following exception:

System.FormatException: Input string was not in a correct format.

Can anybody tell me why? I'm using C#, asp.net, mvc2, and .net framework 4

Answer 1

Two problems. Firstly you should not be escaping the first : . This is necessary as a separator and should not be escaped.

The second is that HH should be hh .

This runs without errors:

string.Format(@"{0:hh\:mm}", new TimeSpan(0))

Answer 2

Your format string uses HH - it should be hh .

See Custom TimeSpan Format Strings on MSDN.

Additionally, your first : shouldn't be escaped - it is part of the placeholder 0 , not a literal.

Together:

string.Format(@"{0:hh\:mm}", new TimeSpan(0))

Answer 3

使用时应使用hh而不是HH。

Answer 4

Check the specification here: http://msdn.microsoft.com/en-us/library/ee372286.aspx

You should use hh instead of HH, eg:

var str = string.Format(@"{0:hh\\:mm}", new TimeSpan(2,2,0));