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Can someone help me with this ngIf condition, I'm trying to hide the logout when key doesn't exist and show it when its exist in the localStorage. I'm getting confused about multiple conditions in the ngIf but the checks are correct.

This check is being used as a directive.

checkSession() {
  var checkKey = localStorage.getItem('sessionKey');
  if(checkKey == null){
      var showLogout = false;
      console.log('null key: ', checkKey);
  } else {
      showLogout = true;
      //this check will only be available once the user is logged in
      console.log('key exist: ' checkKey);
  }

}

Html

 <a (click)="logout()" title="Logout" *ngIf="showLogout || (!showLogout && !showLogout)">
    <i class="fa fa-sign-out fa-2x" aria-hidden="true" ></i>
 </a>

Can someone help me with this ngIf condition, I'm trying to hide the logout when key doesn't exist and show it when its exist in the localStorage. I'm getting confused about multiple conditions in the ngIf but the checks are correct.

This check is being used as a directive.

checkSession() {
  var checkKey = localStorage.getItem('sessionKey');
  if(checkKey == null){
      var showLogout = false;
      console.log('null key: ', checkKey);
  } else {
      showLogout = true;
      //this check will only be available once the user is logged in
      console.log('key exist: ' checkKey);
  }

}

Html

 <a (click)="logout()" title="Logout" *ngIf="showLogout || (!showLogout && !showLogout)">
    <i class="fa fa-sign-out fa-2x" aria-hidden="true" ></i>
 </a>

• javascript
• angular

Share Improve this question Follow edited Aug 16, 2016 at 9:36 Günter Zöchbauer 658k233233 gold badges2.1k2.1k silver badges1.6k1.6k bronze badges asked Aug 16, 2016 at 9:34 nCorenCore 2,09777 gold badges3131 silver badges5959 bronze badges

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1 Answer 1

Sorted by: Reset to default 4

It seems what you want is

export class MyComponent {

  /// other stuff

  showLogout:boolean = false;

  checkSession() {
    var checkKey = localStorage.getItem('sessionKey');
    if(checkKey == null){
        this.showLogout = false; // changed
        console.log('null key: ', checkKey);
    } else {
        this.showLogout = true; // changed
        //this check will only be available once the user is logged in
        console.log('key exist: ' checkKey);
    }
  }
}

A local variable won't be available in the template. The template can only access top-level properties and methods of your ponents class directly.

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