Logical operators are not working in JS file

Question

Everything is fine I am able to fetching the data from SharePoint 2013 List using CAML query in my js file. But when i try to get the data via dropdown conditions my code is executing in the else statement .Can aone help me what went wrong in my below code

 alert('entered into SVV function');
var clientContext = new SP.ClientContext.get_current();
/*alert('Go Client Context');*/
var oList = clientContext.get_web().get_lists().getByTitle('Execution');
var drbregionvalue= document.getElementById("drbregion").value;
var drbfunctionsvalue= document.getElementById("drbfunctions").value;
var drbmonthvalue=document.getElementById("drbmonth").value;
var allvalue="ALL";

var camlQuery = new SP.CamlQuery();

if(drbfunctionsvalue!=allvalue && drbregionvalue!=allvalue)
{
alert('Your dropdown values for both are all');
camlQuery.set_viewXml("<View><Query><Where><And><Eq><FieldRef Name='Region'/><Value Type='Text'>" + drbregionvalue + "</Value></Eq><Eq><FieldRef Name='Title'/><Value Type='Text'>" + drbfunctionsvalue + "</Value></Eq></And></Where></Query></View>");
}
else
{
alert('Among 1 Dropdowns You selected all');

}

Answer 1

It's not all that clear what your conditions are supposed to be, but based on the alert messages you have, these make the most sense to me.

if(drbfunctionsvalue==allvalue && drbregionvalue==allvalue) //AND => both
{
    alert('Your dropdown values for both are all');
    camlQuery.set_viewXml("<...omitted...\>");
}
else if(drbfunctionsvalue==allvalue || drbregionvalue==allvalue) //OR => one
{
    alert('Among 1 Dropdowns You selected all');

}else{
    alert('Neither dropdown selected all');  //none selected all
}