Question

页 - 不found.component.ts

import { FormsModule, NgModel } from '@angular/forms';
import { ChangeDetectorRef, Component, ElementRef, OnInit, Renderer2, ViewChild, ViewEncapsulation } from '@angular/core';
import {CommonModule} from '@angular/common';
import {NgModule} from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { element } from 'protractor';
import { SplitButtonModule } from "primeng/primeng";
import { Router } from '@angular/router';

@Component({
  selector: 'app-page-not-found',
  templateUrl: './page-not-found.component.html',
  styleUrls: ['./page-not-found.component.css']
})
export class PageNotFoundComponent implements OnInit {

  constructor() { }

  ngOnInit() {
  }

}

page-not-found.component.html

<p *ngif=true>
  page-not-found works!
</p>

问题是*ngif无效。我重新启动了系统并清除了缓存。我收到以下错误：

Uncaught Error: Template parse errors:
Property binding ngif not used by any directive on an embedded template. Make sure that the property name is spelled correctly and all directives are listed in the "@NgModule.declarations". ("[ERROR->]<p *ngif=true>
  page-not-found works!
</p>

Answer 1

请使用：

<p *ngIf="true">
  page-not-found works!
</p>

*ngIf不正确*ngif

Answer 2

每当你有像* ngIf，[value =]或（改变）这样的角度语法时，方程式的另一端应该用引号括起来。这告诉angular要在组件中查找您的值。因此，我建议您在组件中放置一个字段，如下所示：

truthy = true;

然后：

<p *ngIf="truthy">
  page-not-found works!
</p>

如果你不用引号括起来，它会假定它是一个字符串文字，并且可能不会给你你想要的结果。

* ngIf不能一直工作

2 个答案: