上天赐予了你宝贵的生命，必定要让你在一生中，坚持，奋斗到最后一秒，燃烧尽生命的火焰。
本文实例为大家分享了js实现图片查看器的具体代码，供大家参考，具体内容如下
1. 前言
网上已经有不少成熟的图片查看器插件，如果是单纯想要点击图片放大预览的话，可以直接使用插件。例如viewerjs
但是，当打开图片后还需要对图片进行一些像删除、下载、标记等业务层面上的操作，使用插件就显得不那么便捷，于是决定自己简单写个图片查看器
2. 设计思路
项目中用的是vue+iview，于是使用Modal弹窗组件做为播放器的盒子，考虑需要用到的基本功能有：放大缩小、监听鼠标滚轮放大缩小、拖拽、全屏查看、查看上/下一张、双击图片回到初始大小和初始位置
3. 完成效果
4. 代码思路
html部分：
<Modal
id="picture_viewer_modal"
v-model="visible"
:mask-closable = "false"
@on-cancel="cancel()"
footer-hide
width="70%"
:fullscreen="fullscreen"
>
<div class="wrap">
<p class="num_tip">第 {{index+1}}/{{picArr.length}} 张</p>
<!-- 查看图片的盒子 -->
<div id="father" class="box">
<img id="box" class="img_max img_auto" @dblclick="getDefault()" :src="row.src">
<!-- 查看上一张 -->
<span class="next_btn btn_left" @click="left()"></span>
<!-- 查看下一张 -->
<span class="next_btn btn_right" @click="right()"></span>
</div>
<!-- 按钮条 -->
<div class="tool_bar">
<!-- 裁剪 -->
<span class="tool_btn btn_1" @click="cutPic()"></span>
<!-- 全屏 -->
<span class="tool_btn btn_2" @click="fullScreen()"></span>
<!-- 放大 -->
<span class="tool_btn btn_3" @click="big()"></span>
<!-- 缩小 -->
<span class="tool_btn btn_4" @click="small()"></span>
<!-- 下载 -->
<span class="tool_btn btn_5" @click="download()"></span>
<!-- 选中 -->
<span class="tool_btn btn_8" @click="choose()"></span>
<!-- 删除 -->
<span class="tool_btn btn_9" @click="del(row.id)"></span>
</div>
</div>
</Modal>
js部分：
props: {
picList:Array,
rowData:Object
},
data() {
return {
//弹窗显隐
visible: false,
//当前查看的图片
row: {},
//当前查看的图片在数组中的位置
index: 0,
//所有图片
picArr: [],
//是否全屏
fullscreen: false,
};
},
watch: {
//监听弹窗打开事件
modal(val) {
this.visible = val;
if(val){
this.init();
this.getObj();
}
},
},
mounted(){
this.move();
},
methods: {
/**
* 打开弹窗后，获取传入弹窗组件的数据
*/
getObj(){
this.row = this.rowData.row;
this.index = this.rowData.index;
this.picArr = this.picList;
},
/**
* 初始化
*/
init(){
this.fullscreen = false;
//重新打开后图片要重置回默认大小和居中
this.getDefault();
},
/**
* 双击图片恢复默认大小、位置
*/
getDefault(){
var image = document.getElementById("box");
image.classList.add('img_max');
image.classList.add('img_auto');
box.style.left = '50%';
box.style.top = '50%';
box.style.transform = 'translate(-50%,-50%)';
},
/**
* 拖拽移动
*/
move(){
var thiz = this;
thiz.$nextTick(() => {
var box = document.getElementById("box");
var fa = document.getElementById('father');
// 图片移动效果
box.onmousedown=function(ev) {
var oEvent = ev;
// 浏览器有一些图片的默认事件,这里要阻止
oEvent.preventDefault();
var disX = oEvent.clientX - box.offsetLeft;
var disY = oEvent.clientY - box.offsetTop;
fa.onmousemove=function (ev) {
oEvent = ev;
oEvent.preventDefault();
var x = oEvent.clientX - disX;
var y = oEvent.clientY - disY;
// 图形移动的边界判断
// x = x <= 0 ? 0 : x;
// x = x >= fa.offsetWidth-box.offsetWidth ? fa.offsetWidth-box.offsetWidth : x;
// y = y <= 0 ? 0 : y;
// y = y >= fa.offsetHeight-box.offsetHeight ? fa.offsetHeight-box.offsetHeight : y;
box.style.left = x + 'px';
box.style.top = y + 'px';
//取消居中效果
// box.style.transform = 'translate(0,0)';
};
// 图形移出父盒子取消移动事件,防止移动过快触发鼠标移出事件,导致鼠标弹起事件失效
fa.onmouseleave = function () {
fa.onmousemove = null;
fa.onmouseup = null;
};
// 鼠标弹起后停止移动
fa.onmouseup=function() {
fa.onmousemove = null;
fa.onmouseup = null;
}
}
//监听鼠标滚轮放大缩小
box.addEventListener("mousewheel", MouseWheelHandler, false);// IE9, Chrome, Safari, Opera
box.addEventListener("DOMMouseScroll", MouseWheelHandler, false);// Firefox
function MouseWheelHandler(e) {
// cross-browser wheel delta
var e = window.event || e; // old IE support
var delta = Math.max(-1, Math.min(1, (e.wheelDelta || -e.detail)));//IE、Opera、Safari、Chrome e.wheelDelta,Firefox中 e.detail 判断是向上还是向下滚动负值delta取-1 正值delta取1
box.height = Math.max(100, Math.min(2500, box.height + (50 * delta)));
box.classList.remove('img_max');
box.classList.remove('img_auto');
return false;
}
});
},
/**
* 全屏
*/
fullScreen(){
//控制弹窗全屏
this.fullscreen = !this.fullscreen;
//图片恢复默认大小、位置
this.getDefault();
},
/**
* 放大
*/
big(){
var image = document.getElementById("box");
if (image.height <= 2500) {
image.height = image.height + 40;
}
image.classList.remove('img_max');
image.classList.remove('img_auto');
},
/**
* 缩小
*/
small(){
var image = document.getElementById("box");
if (image.height > 100) {
image.height = image.height - 40;
}
image.classList.remove('img_auto');
},
/**
* 查看上一张
*/
left(){
var thiz = this;
if(thiz.index == 0){
//如果是第一张，则跳到最后一张
thiz.index = thiz.picArr.length - 1;
thiz.row = thiz.picArr[thiz.index];
}else{
thiz.index = thiz.index - 1;
thiz.row = thiz.picArr[thiz.index];
}
//查看上下一张的时候，图片回到初始大小和位置，这里会闪烁，待优化
this.getDefault();
},
/**
* 查看下一张
*/
right(){
var thiz = this;
if(thiz.index == thiz.picArr.length-1){
//如果是最后一张，则跳到第一张
thiz.index = 0;
thiz.row = thiz.picArr[thiz.index];
}else{
thiz.index = thiz.index + 1;
thiz.row = thiz.picArr[thiz.index];
}
//查看上下一张的时候，图片回到初始大小和位置，这里会闪烁，待优化
this.getDefault();
},
}
css部分：
//less
@pictureBg: #fff,
@pictureBorder: #fff,
@pictureCloseBg: #fff,
@pictureCloseBorder: #1A82FD,
@pictureClose: #1A82FD,
@pictureBtn1: url('../assets/map/view_image/icon_cut_blue.png')
@pictureBtn2: url('../assets/map/view_image/icon_move_blue.png')
@pictureBtn3: url('../assets/map/view_image/icon_zoom_blue.png')
@pictureBtn4: url('../assets/map/view_image/icon_reduce_blue.png')
@pictureBtn5: url('../assets/map/view_image/icon_download_blue.png')
@pictureBtn6: url('../assets/map/view_image/icon_play_blue.png')
@pictureBtn7: url('../assets/map/view_image/icon_video_blue.png')
@pictureBtn8: url('../assets/map/view_image/icon_chose_blue.png')
@pictureBtn9: url('../assets/map/view_image/icon_delete_blue.png')
@pictureBtnHov1: url('../assets/map/view_image/icon_cut_hov.png')
@pictureBtnHov2: url('../assets/map/view_image/icon_move_hov.png')
@pictureBtnHov3: url('../assets/map/view_image/icon_zoom_hov.png')
@pictureBtnHov4: url('../assets/map/view_image/icon_reduce_hov.png')
@pictureBtnHov5: url('../assets/map/view_image/icon_download_hov.png')
@pictureBtnHov6: url('../assets/map/view_image/icon_play_hov.png')
@pictureBtnHov7: url('../assets/map/view_image/icon_video_hov.png')
@pictureBtnHov8: url('../assets/map/view_image/icon_chose_hov.png')
@pictureBtnHov9: url('../assets/map/view_image/icon_delete_hov.png')
#picture_viewer_modal{
.ivu-modal{
//覆盖modal关闭按钮样式
.ivu-modal-close{
right: -12px;
top: -12px;
border-radius: 100px;
background: @pictureCloseBg;
border:1px solid @pictureCloseBorder;
.ivu-icon-ios-close{
font-size: 24px;
color: @pictureClose;
}
}
//覆盖modal弹窗盒子样式
.ivu-modal-content{
background: @pictureBg;
border:1px solid @pictureBorder;
border-radius: 0;
.ivu-modal-body{
height: 80vh;
padding: 35px 15px 0;
overflow: hidden;
}
// 内容样式
.wrap{
height: 100%;
>.num_tip{
color: @pictureClose;
position: absolute;
top: 10px;
left: 15px;
z-index: 9;
}
//图片盒子样式
>.box{
height: calc(100% - 20px - 1.2vw);
position: relative;
//展示的图片样式
>img{
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
cursor: move;
&.img_auto{
width: auto;
height: auto;
}
&.img_max{
max-height: 100%;
max-width: 100%;
}
}
//上/下一张按钮样式
>.next_btn{
display: block;
width: 3vw;
height: 3vw;
position: absolute;
top: 50%;
margin-top: -1.5vw;
cursor: pointer;
transition: all 0.2s;
&.btn_left{
left: 6px;
background: url('../../../assets/map/view_image/btn_left.png') no-repeat;
background-size: 100% 100%;
&:hover{
background: url('../../../assets/map/view_image/btn_left_hov.png') no-repeat;
background-size: 100% 100%;
}
}
&.btn_right{
right: 6px;
background: url('../../../assets/map/view_image/btn_right.png') no-repeat;
background-size: 100% 100%;
&:hover{
background: url('../../../assets/map/view_image/btn_right_hov.png') no-repeat;
background-size: 100% 100%;
}
}
}
}
//底部工具条样式
>.tool_bar{
text-align: center;
font-size: 0;
position: relative;
z-index: 9;
.tool_btn{
font-size: 12px;
display: inline-block;
width: 1.2vw;
height: 1.2vw;
margin: 10px 0.8vw;
transition: all 0.2s;
cursor: pointer;
}
.btn_1{
background: @pictureBtn1 no-repeat;
background-size: 100% 100%;
&:hover{
background: @pictureBtnHov1 no-repeat;
background-size: 100% 100%;
}
}
.btn_2{
background: @pictureBtn2 no-repeat;
background-size: 100% 100%;
&:hover{
background: @pictureBtnHov2 no-repeat;
background-size: 100% 100%;
}
}
.btn_3{
background: @pictureBtn3 no-repeat;
background-size: 100% 100%;
&:hover{
background: @pictureBtnHov3 no-repeat;
background-size: 100% 100%;
}
}
.btn_4{
background: @pictureBtn4 no-repeat;
background-size: 100% 100%;
&:hover{
background: @pictureBtnHov4 no-repeat;
background-size: 100% 100%;
}
}
.btn_5{
background: @pictureBtn5 no-repeat;
background-size: 100% 100%;
&:hover{
background: @pictureBtnHov5 no-repeat;
background-size: 100% 100%;
}
}
.btn_6{
background: @pictureBtn6 no-repeat;
background-size: 100% 100%;
&:hover{
background: @pictureBtnHov6 no-repeat;
background-size: 100% 100%;
}
}
.btn_7{
background: @pictureBtn7 no-repeat;
background-size: 100% 100%;
&:hover{
background: @pictureBtnHov7 no-repeat;
background-size: 100% 100%;
}
}
.btn_8{
background: @pictureBtn8 no-repeat;
background-size: 100% 100%;
&:hover{
background: @pictureBtnHov8 no-repeat;
background-size: 100% 100%;
}
}
.btn_9{
background: @pictureBtn9 no-repeat;
background-size: 100% 100%;
&:hover{
background: @pictureBtnHov9 no-repeat;
background-size: 100% 100%;
}
}
}
}
}
//弹窗全屏样式
&.ivu-modal-fullscreen{
.ivu-modal-close{
right: 0;
top: 0;
}
.ivu-modal-content{
.ivu-modal-body{
height: 100vh;
overflow: hidden;
}
}
}
}
}
以上就是js实现图片查看器。坎坷之身须怀壮志之情，穷困之境应无颓唐之意。更多关于js实现图片查看器请关注haodaima.com其它相关文章！