Get Query string values from Javascript

function QuseryStringValue(QID) {

// Fetch the query string.
var QStringOriginal = window.location.search.substring(1);

// Change the case as querystring id values normally case insensitive.
QString = QStringOriginal.toLowerCase();
var qsValue = '';

// QueryString ID.
QID = QID.toLowerCase();
// Start & end point of the QueryString Value.
var qsStartPoint = QString.indexOf(QID);
if (qsStartPoint != -1) {

qsValue = QStringOriginal.substring(qsStartPoint + QID.length + 1);
// Search for '&' in the query string;
var qsEndPoint = qsValue.indexOf('&');
if (qsEndPoint != -1) {

// retrive the QueryString value & Return it.
qsValue = qsValue.substring(0, qsEndPoint);

}
else if (qsValue.indexOf('#') != -1) {

// Search for '#' in the query string;
qsEndPoint = qsValue.indexOf('&');
// retrive the QueryString value & Return it.
qsValue = qsValue.substring(0, qsEndPoint);

}
else {

qsValue = qsValue.substring(0);

}

}

return qsValue;
}