Question 293243 in Javascript Question posted in
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Javascript saying a key does not exist in an object even though it does

I am creating an admin panel.
For some reason, my code returns an error saying banned users does not exist even though it is in the Object. This confuses me alot and I dont know how to solve it. I got the error originally that says TypeError: Cannot read properties of undefined (reading 'forEach'), and when I logged the key banned_users, it returns undefined. I even tried logging the data in the console after it, but it still has the key banned_users in it.

Here is my code that handles the response:

fetch('/admin_info')
    .then(response => response.json())
    .then(data => {
      console.log(data)
      data.admins.forEach((admin) => {
        var list_admin = document.createElement('li');
        if (admin != data.owner && admin != data.admin_username) {
          list_admin.className = 'list_admin';
          list_admin.onclick = function (){
            remove_admin(admin)
          }
        }
        list_admin.id = `admin_${admin}`;
        if (admin == data.owner){
          list_admin.innerText = `${admin} (Owner)`
        }else{
          list_admin.innerText = admin
        }
        admin_list.appendChild(list_admin);
      });
    })
      //Problem Code
      banned_users = data.banned_users
      console.log(data.banned_users)
      banned_users.forEach((user) => {
      var banned_user = document.createElement('li');
      banned_user.className = 'banned_user';
      banned_user.innerText = user
      banned_user.appendChild(banned_list)
    //
    })
    .catch(error => {
      error_display.style.display = 'block';
      error_text.innerText = `Admin Panel failed to load: ${error}`;
    });
}

This is the JSON it is receiving as a response:

"admin_username":"Username",
"admins":["Username1","Username2"],
"banned_users":{"test":{}},"owner":"Username"}

Does anyone have a solution to this issue?
Edit: I am also having an issue with saying data.banned_users or data["banned_users"] since it’s not getting the key from the JSON and returning undefined for some reason

Tags:

2

Answers


  1. 0

    Your banned_users is an Object. Objects don’t have a forEach method, only Arrays do. Instead of forEach, use a for … in loop.

      for (let user in banned_users) {
    var banned_user = document.createElement('li');
      banned_user.className = 'banned_user';
      banned_user.innerText = user
      banned_user.appendChild(banned_list)
}

    Does this code work? I don’t see banned_list referred to anywhere else. But the structure stands…

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  2. 0

    In your response, banned_users is an Object. Objects do not have a forEach method. Instead, you can try something like this:

    for (var user in banned_users) {
    var banned_user = document.createElement('li');
    banned_user.className = 'banned_user';
    banned_user.innerText = user
    banned_user.appendChild(banned_list)
}
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