本文实例为大家分享了Angular实现二级导航栏的具体代码，供大家参考，具体内容如下
1、将菜单放入数据库：
模拟放到该路径下：
src/assets/json/header.json
{
"siteName": "PGG娱乐健身中心",
"menu":[
{
"id":"1",
"menuName":"首页",
"menuChildren": [{}],
"showSubMenu": false
},
{
"id":"2",
"menuName":"健身中心",
"menuChildren": [
{
"itemId": "1",
"menuChidrenItem": "居室器械健身"
},
{
"itemId": "2",
"menuChidrenItem": "野外运动"
},
{
"itemId": "3",
"menuChidrenItem": "健身小知识"
}
],
"showSubMenu": false
},
{
"id":"3",
"menuName":"休闲娱乐",
"menuChildren": [
{
"itemId": "1",
"menuChidrenItem": "养生钓鱼"
},
{
"itemId": "2",
"menuChidrenItem": "野炊烧烤"
},
{
"itemId": "3",
"menuChidrenItem": "真人野战"
}
],
"showSubMenu": false
},
{
"id":"4",
"menuName":"订单中心",
"menuChildren": [
{
"itemId": "1",
"menuChidrenItem": "所有订单"
},
{
"itemId": "2",
"menuChidrenItem": "已完成订单"
},
{
"itemId": "3",
"menuChidrenItem": "未完成订单"
}
],
"showSubMenu": false
},
{
"id":"5",
"menuName":"个人中心",
"menuChildren": [
{
"itemId": "1",
"menuChidrenItem": "用户信息修改"
}
],
"showSubMenu": false
}
]
}ts接受数据，并处理：
import { Component, OnInit } from '@angular/core';
import { HttpClient, HttpClientModule } from '@angular/common/http';
@Component({
selector: 'app-header',
templateUrl: './header.component.html',
styleUrls: ['./header.component.css']
})
export class HeaderComponent implements OnInit {
headData: any;
constructor(
private http: HttpClient
) { }
ngOnInit(): void {
// http://localhost:4200/assets/json/header.json 可访问
this.http.get('/assets/json/header.json').subscribe(data => {
this.headData = data;
console.log(this.headData.menu);
});
}
showSubMenu(item: any, index: any): void {
// 设置当前子菜单显示
item.showSubMenu = true;
}
notShowSubMenu(item: any, index: any): void {
// 设置当前子菜单不显示
item.showSubMenu = false;
}
}html显示控制，利用ngstyle控制:
<div class="menu_container">
<div id="top_title">{{headData.siteName}}</div>
<div id="menu" *ngFor="let item of headData.menu, let i = index">
<!-- 第一个参数为类名称，第二个参数为boolean值，如果为true就添加第一个参数的类-->
<ul [ngClass]="{'sumMenu': item.showSubMenu}">
<!--mouseleave mouseout供选则-->
<li class="top_nav nav_1" (mouseenter)="showSubMenu(item ,i)" (mouseleave)="notShowSubMenu(item, i)">
<span>{{item.menuName}}</span>
<dl *ngFor="let child of item.menuChildren, let k = index"
[ngStyle]="{'display': item.showSubMenu ? 'block':'none','margin-left': '-2.6rem'}">
<dd>{{child.menuChidrenItem}}</dd>
</dl>
</li>
</ul>
</div>
</div>实际效果：
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持Devmax。