Why does the variable's value reset to empty when leaving the function?

Question

Why does the variable's value reset to empty when leaving the function?

I encountered an issue with my api request that is included in a function within my Service script. Despite defining the variable "curruser" outside of the function to retain its value, I noticed that it becomes empty after exiting the script.

services.js

function fbUserInfo() {
  ngFB.api({
    path: '/me',
    params: {
      fields: '/*params*/'
    }
  }).then(
    function(user) {
      curruser = user;

      $http.get(/*send GET request to my server*/).success(function(response) {
        if (response.length < 20) {
          curruser.firsttime = true;
        } else {
          curruser.firsttime = false;
        }
        console.log(curruser);
        console.log("1");
      });
    },

    function(error) {
      alert('Facebook error: ' + error.error_description);
    });
}

Although the console.log displays the correct JSON object retrieved from Facebook, when I attempt to return it in the statement:

return {
  userInfo: function() {
    fbUserInfo();
    console.log(curruser);
    return curruser;
  }

it shows that curruser is an empty object. I made sure to include

var curruser;

at the beginning of the ".factory" as well.

javascript angularjs http ionic-framework

Answer 1

Answer №1

Ensure to utilize the then() method as fbUserInfo() is an asynchronous function.

return {
  userInfo: function() {
    $.when(fbUserInfo()).then(
function(user) {
  curruser = user;

  $http.get(/*send GET request to my server*/).success(function(response) {
    if (response.length < 20) {
      curruser.firsttime = true;
    } else {
      curruser.firsttime = false;
    }
    console.log(curruser);
    console.log("1");
  });
},

function(error) {
  alert('Facebook error: ' + error.error_description);
}).then(function(){
 console.log(curruser);
    return curruser;
})

  }

Answer 2

Ensure to utilize the then() method as fbUserInfo() is an asynchronous function.

return {
  userInfo: function() {
    $.when(fbUserInfo()).then(
function(user) {
  curruser = user;

  $http.get(/*send GET request to my server*/).success(function(response) {
    if (response.length < 20) {
      curruser.firsttime = true;
    } else {
      curruser.firsttime = false;
    }
    console.log(curruser);
    console.log("1");
  });
},

function(error) {
  alert('Facebook error: ' + error.error_description);
}).then(function(){
 console.log(curruser);
    return curruser;
})

  }

Answer 3

Answer №2

Not yet tested, but it has the potential to work.

    var currentUser;
    function getFacebookUserInfo( callback ) {
      ngFB.api({
        path: '/me',
        params: {
          fields: '/*params*/'
        }
      }).then(
        function(user) {
          currentUser = user;

          $http.get(/*send GET request to my server*/).success(function(response) {
            if (response.length < 20) {
              currentUser.firstTimeUser = true;
            } else {
              currentUser.firstTimeUser = false;
            }
            console.log(currentUser);
            console.log("1");
            callback(currentUser);
          });
        },

        function(error) {
          alert('Facebook error: ' + error.error_description);
        });
    }


return {
  userInfo: function( callback ) {
    getFacebookUserInfo( function(data){
       console.log(data);
       callback(data);
    });
  }

Answer 4

Not yet tested, but it has the potential to work.

    var currentUser;
    function getFacebookUserInfo( callback ) {
      ngFB.api({
        path: '/me',
        params: {
          fields: '/*params*/'
        }
      }).then(
        function(user) {
          currentUser = user;

          $http.get(/*send GET request to my server*/).success(function(response) {
            if (response.length < 20) {
              currentUser.firstTimeUser = true;
            } else {
              currentUser.firstTimeUser = false;
            }
            console.log(currentUser);
            console.log("1");
            callback(currentUser);
          });
        },

        function(error) {
          alert('Facebook error: ' + error.error_description);
        });
    }


return {
  userInfo: function( callback ) {
    getFacebookUserInfo( function(data){
       console.log(data);
       callback(data);
    });
  }

Why does the variable's value reset to empty when leaving the function?

Answer №1

Answer №2

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