功能齊全的輪播---基於angular7

輪播有的功能,應該都有

angular2及以上的版本應該均可以

動畫效果用的是angular自帶的animations

css沒有作進一步的處理,專一於js

作過測試應該沒有bug

功能

1.圖片自動輪播

2.每張圖片對應下面的小圓圈,紅色表明當前選中圖片

3.前進和後退按鈕作了節流處理

代碼

html

<p>
  carousel works!
</p>
<ul  [@carousel]='state' >
  <li class='imgP' *ngFor='let img of imgs' (mouseenter)='stop()'
      (mouseleave)='start()'
    >
      <!---->
      <div *ngIf='img.state'>
            <img [src]="url+img.name" >
      </div>
        
    </li> 
    
</ul>
<div >
    <div class='circle' [class.color]='img.state' *ngFor='let img of imgs'
      (mouseenter)="circleEnter(img.id)" (mouseleave)='circleLeave()'
    >
            
    </div>
    <div class='btn' (mouseenter)='stop()' (mouseleave)='start()'>
        <input type="button" value="go" (click)="go()">
        <input type="button" value="back" (click)="back()">
    </div>
</div>

js

import { Component, OnInit } from '@angular/core';
import {trigger,style,transition,query,animate,group} from '@angular/animations'
@Component({
  selector: 'app-carousel',
  templateUrl: './carousel.component.html',
  styleUrls: ['./carousel.component.css'],
    animations:[
      trigger('carousel',[
          transition(':increment',[
              group([
                  query(':enter',[
                        style({transform:'translateX(-100%)'}),
                        animate('1s')
                    ]),
                    query(':leave',[
                        animate('1s',style({transform:'translateX(100%)'}))
                    ])
                ]) 
            ]),
            transition(':decrement',[
              group([
                  query(':enter',[
                        style({transform:'translateX(100%)'}),
                        animate('1s')
                    ]),
                    query(':leave',[
                        animate('1s',style({transform:'translateX(-100%)'}))
                    ])
                ]) 
            ]),
        ])
    ]
})
export class CarouselComponent implements OnInit {
  url:string='../../../assets/'
  imgs=[
      {id:1,name:'1.jpg',state:true},
        {id:2,name:'2.jpg',state:false},
        {id:3,name:'3.jpg',state:false}
    ]
    state=0;
    id:number;
    i=0;
    switch=true
    execTime:number
  constructor() { }
  fn(){
      this.i++;
        if(this.i>this.imgs.length-1){
            this.i=0;
        }
      this.imgs.forEach(val=>{val.state=false})
        this.imgs[this.i].state=true;
        this.state+=0.1;
    }
  ngOnInit() {
    this.id=setInterval(this.fn.bind(this),3000) 
  }
  stop(){
      clearInterval(this.id)
    }
    start(){
      this.id=setInterval(this.fn.bind(this),3000) 
    }
    circleEnter(id){
      //console.log(id);
        this.i=id-1;
        this.imgs.forEach(val=>{val.state=false})
        this.imgs[id-1].state=true;
        //this.state+=0.1;
      this.stop();
    }
    circleLeave(){
      this.start();
    }
    go(){
      this.throttle(this.fn.bind(this),1500)
      //this.fn()
    }
    back(){
      let fn=function(){
          //console.log('exec fn');
          this.i--;
            if(this.i<0){
                this.i=this.imgs.length-1;
            }
            this.imgs.forEach(val=>{val.state=false})
            this.imgs[this.i].state=true;
            this.state-=0.1;
        }
      this.throttle(fn.bind(this),1500)
    }
    
  throttle(fn,interval){
        if(new Date().getTime()-this.execTime>interval){this.switch=true}
        console.log(this.switch);
      if(this.switch){
            fn();
            this.switch=false;
            this.execTime=new Date().getTime();
        }
        
    }
    
}

css

ul{
  position:relative;
  height:200px;
}
.imgP{
  position:absolute;
  list-style:none;
}
.circle{
  width:10px;
  height:10px;
  border-radius:50%;
  border:1px solid #000;
  float:left;
}
.color{
  background-color:red;
}