get url parameters with javascript

getParameterByName.js

function getParameterByName( name,href )
{
  name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
  var regexS = "[\\?&]"+name+"=([^&#]*)";
  var regex = new RegExp( regexS );
  var results = regex.exec( href );
  if( results == null )
    return "";
  else
    return decodeURIComponent(results[1].replace(/\+/g, " "));
}

getParameterByName('loan', window.location)
"1234"