I frequently make use of Request.QueryString[]
variables.
In my Page_load
I often do things like:
int id = -1;
if (Request.QueryString["id"] != null) {
try
{
id = int.Parse(Request.QueryString["id"]);
}
catch
{
// deal with it
}
}
DoSomethingSpectacularNow(id);
It all seems a bit clunky and rubbish. How do you deal with your Request.QueryString[]
s?
Below is an extension method that will allow you to write code like this:
int id = request.QueryString.GetValue<int>("id");
DateTime date = request.QueryString.GetValue<DateTime>("date");
It makes use of TypeDescriptor
to perform the conversion. Based on your needs, you could add an overload which takes a default value instead of throwing an exception:
public static T GetValue<T>(this NameValueCollection collection, string key)
{
if(collection == null)
{
throw new ArgumentNullException("collection");
}
var value = collection[key];
if(value == null)
{
throw new ArgumentOutOfRangeException("key");
}
var converter = TypeDescriptor.GetConverter(typeof(T));
if(!converter.CanConvertFrom(typeof(string)))
{
throw new ArgumentException(String.Format("Cannot convert '{0}' to {1}", value, typeof(T)));
}
return (T) converter.ConvertFrom(value);
}