public class PageCannotFindException : ApplicationException
{
public PageCannotFindException(string pageName)
: base("Cannot find page: " + pageName)
{
}
public PageCannotFindException(string pageName, Exception innerException)
: base("Cannot find page: " + pageName, innerException)
{
}
}
上面是一个简单的用户异常类

try
{
...
}
Catch(PageCannotFindException  ex)
{
...
}

Catch(Exception ex)
{
throw new PageCannotFindException(pageName, ex);
}