diff --git a/components/select/demo/custom-template.ts b/components/select/demo/custom-template.ts
index 602e4c37cf6..a3dd15892b2 100644
--- a/components/select/demo/custom-template.ts
+++ b/components/select/demo/custom-template.ts
@@ -3,21 +3,23 @@ import { Component } from '@angular/core';
 @Component({
   selector: 'nz-demo-select-custom-template',
   template: `
-    <nz-select style="width: 200px;" nzAllowClear nzPlaceHolder="Select OS" [(ngModel)]="selectedOS" [nzCustomTemplate]="custom">
+    <nz-select
+      style="width: 200px;"
+      nzAllowClear
+      nzPlaceHolder="Select OS"
+      [(ngModel)]="selectedOS"
+      [nzCustomTemplate]="custom"
+    >
       <nz-option nzCustomContent nzLabel="Windows" nzValue="windows"><i nz-icon type="windows"></i> Windows</nz-option>
       <nz-option nzCustomContent nzLabel="Mac" nzValue="mac"><i nz-icon type="apple"></i> Mac</nz-option>
       <nz-option nzCustomContent nzLabel="Android" nzValue="android"><i nz-icon type="android"></i> Android</nz-option>
     </nz-select>
     <ng-template #custom let-selected>
-      <div>
-        Label: {{selected.nzLabel}}
-      </div>
-      <div>
-        Value: {{ selected.nzValue }}
-      </div>
+      <div>Label: {{ selected.nzLabel }}</div>
+      <div>Value: {{ selected.nzValue }}</div>
     </ng-template>
   `
 })
 export class NzDemoSelectCustomTemplateComponent {
-  selectedOS;
+  selectedOS = null;
 }