fix(module:dropdown): fix unsubscribe undefined bug (#464)

close #269
NG-ZORRO · Oct 21, 2017 · a0dcad3 · a0dcad3
1 parent 704aa45
commit a0dcad3
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/src/components/dropdown/nz-dropdown.component.ts b/src/components/dropdown/nz-dropdown.component.ts
@@ -154,7 +154,9 @@ export class NzDropDownComponent implements OnInit, OnDestroy, AfterViewInit {
   }
 
   ngOnDestroy() {
-    this._subscription.unsubscribe();
+    if (this._subscription) {
+      this._subscription.unsubscribe();
+    }
   }
 
   ngAfterViewInit() {