Get the Parameters From the Form URL in JavaScript

function getSearchParameters() {
      var parameterstring = window.location.search.substr(1);
      return parameterstring != null && parameterstring != "" ? transformToAssocArray(parameterstring) : {};
}

function transformToAssocArray( parameterstring ) {
    var params = {};
    var prmarr = parameterstring.split("&");
    for ( var i = 0; i < prmarr.length; i++) {
        var tmparr = prmarr[i].split("=");
        params[tmparr[0]] = tmparr[1];
    }
    return params;
}

var params = getSearchParameters();
alert(params.code);


Test with any url having the Parameter

abc.html?code=adslkfjlaksjflsadfsadfsadfsaddfsafsdfasdf&abc=akjdha