Getting Query String Values using JavaScript in SharePoint

The JSRequest class is a JavaScript object that lives on all SharePoint Pages, and allows us to simply and quickly get query string values using JavaScript.

It has 3 fields: QueryString, FileName, and PathName.

• QueryString - is an array of key\value pairs representing the current query string parameters.
• FileName - is a string containing the current name of the current page.
• PathName - is the server relative path of the current page.

Usage:

//First we must call the EnsureSetup method
JSRequest.EnsureSetup(); 

//Get a query string parameter called Id. i.e - "page.aspx?Id=11" will return 11
itemId = JSRequest.QueryString["Id"];

//Get the current page name. i.e - "default.aspx"
itemId = JSRequest.FileName;

//Get the current path name. i.e - "/itaysk/doclib/default.aspx"
itemId = JSRequest.PathName;

Ref: http://blogs.microsoft.co.il/blogs/itaysk/archive/2008/11/30/getting-query-string-parameters-with-javascript-in-sharepoint.aspx

https://www.nothingbutsharepoint.com/sites/devwiki/SP2007Dev/Pages/SharePoint%20JavaScript%20Functions%20Overview.aspx