Lee Kelleher’s Weblog

Most ASP.NET developers know that you can get a key/value pair string from the Request.QueryString object (via the .ToString() method). However that functionality isn’t the same for a generic NameValueCollection object (of which Request.QueryString is derived from).

So how do you take a NameValueCollection object and get a nicely formatted key/value pair string? (i.e. “key1=value1&key2=value2“) … Here’s a method I wrote a while ago:

/// <summary>
/// Constructs a QueryString (string).
/// Consider this method to be the opposite of "System.Web.HttpUtility.ParseQueryString"
/// </summary>
/// <param name="nvc">NameValueCollection</param>
/// <returns>String</returns>
public static String ConstructQueryString(NameValueCollection parameters)
{
	List<String> items = new List<String>();

	foreach (String name in parameters)
		items.Add(String.Concat(name, "=", System.Web.HttpUtility.UrlEncode(parameters[name])));

	return String.Join("&", items.ToArray());
}

Just in case you didn’t know about the System.Web.HttpUtility.ParseQueryString method, it’s a quick way of converting a query (key/value pairs) string back into a NameValueCollection.