What is the best way to update a local variable in JavaScript using Ajax requests?

Question

What is the best way to update a local variable in JavaScript using Ajax requests?

function validate_authentication(){
    var is_authenticated = false;
    $.ajax({
        type: "POST",
        url: "/account/islogin/",
        data: "",
        async: "false",
        success: function(data) {
            if (data == "null") {
                signup();
                is_authenticated = false;
            }
            is_authenticated = true;   
        }
    });
    return is_authenticated;
};

Why does the function always return false, even though is_authenticated=true is executed.

javascript ajax

Answer 1

Answer №1

It seems like the issue lies in running the if statement and setting authenticated to true every time. Perhaps using an if else statement would be more suitable.

function check_login(){
    var authenticated  = false;
    $.ajax({type:"POST",url:"/account/islogin/",data:"",async:false,
        success:function(data){
            if(data=="null"){
                signup();
                authenticated =  false;
            } else {
                authenticated =  true; 
            }
        }
    });
    return authenticated;
};

An alternative approach could be setting authenticated to default to true and only changing it to false when the data is null.

function check_login(){
    var authenticated  = false;
    $.ajax({type:"POST",url:"/account/islogin/",data:"",async:false,
        success:function(data){
            authenticated =  true;
            if(data=="null"){
                signup();
                authenticated =  false;
            }
        }
    });
    return authenticated;
};

Answer 2

It seems like the issue lies in running the if statement and setting authenticated to true every time. Perhaps using an if else statement would be more suitable.

function check_login(){
    var authenticated  = false;
    $.ajax({type:"POST",url:"/account/islogin/",data:"",async:false,
        success:function(data){
            if(data=="null"){
                signup();
                authenticated =  false;
            } else {
                authenticated =  true; 
            }
        }
    });
    return authenticated;
};

An alternative approach could be setting authenticated to default to true and only changing it to false when the data is null.

function check_login(){
    var authenticated  = false;
    $.ajax({type:"POST",url:"/account/islogin/",data:"",async:false,
        success:function(data){
            authenticated =  true;
            if(data=="null"){
                signup();
                authenticated =  false;
            }
        }
    });
    return authenticated;
};

Answer 3

Answer №2

The reason behind the lack of interaction between the authenticated variable in your Ajax function and the one within the check_login() function is due to them being in separate scopes.

Answer 4

The reason behind the lack of interaction between the authenticated variable in your Ajax function and the one within the check_login() function is due to them being in separate scopes.

What is the best way to update a local variable in JavaScript using Ajax requests?

Answer №1

Answer №2

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