String.Format- Exception of type System.Web.HttpUnhandledException was thrown.
Wednesday, August 22, 2007 9:43:12 PM (GMT Daylight Time, UTC+01:00)
Type
System.FormatException
Message
Exception of type 'System.Web.HttpUnhandledException' was thrown.
StackTrace
at System.Text.StringBuilder.FormatError()
at System.Text.StringBuilder.AppendFormat(IFormatProvider provider, String format, Object[] args)
at System.String.Format(IFormatProvider provider, String format, Object[] args)
Error Line
0
Just got that message (or at most "Exception of type 'System.Web.HttpUnhandledException' was thrown")? Puzzled? I was the first time I got it, I've been meaning to post about it for quite some time now so seeing as I got it again today I took the hint.
The error is horrifingly obvious when you know about it, in short, you've no doubt got some code that looks like this:
String.Format(
"<html><head><style type=\"text/css\">body{color: #fff;}</style><body>...");
Can you spot it now? Notice your style declaration is using the curly brackets? Basically String.Format is interpreting that as a placeholder i.e. {0} and is throwing a wobbly.
The solution is simple too, just replace all opening/closing brackets with two i.e:
String.Format(
"<html><head><style type=\"text/css\">body{{color: #fff;}}</style><body>...");
I hope that helps someone out there :)
P.S. Watch out for methods that use String.Format as they may catch you out in the same way -i.e. Subject of System.Net.Mail.MailMessage