一、使用element-ui
代码如下：
<el-upload
class="avatar-uploader"
action="https://jsonplaceholder.typicode.com/posts/"
:show-file-list="false"
:on-success="handleAvatarSuccess"
:before-upload="beforeAvatarUpload">
<img v-if="imageUrl" :src="imageUrl" class="avatar">
<i v-else class="el-icon-plus avatar-uploader-icon"></i>
</el-upload>
<style>
.avatar-uploader .el-upload {
border: 1px dashed #d9d9d9;
border-radius: 6px;
cursor: pointer;
position: relative;
overflow: hidden;
}
.avatar-uploader .el-upload:hover {
border-color: #409EFF;
}
.avatar-uploader-icon {
font-size: 28px;
color: #8c939d;
width: 178px;
height: 178px;
line-height: 178px;
text-align: center;
}
.avatar {
width: 178px;
height: 178px;
display: block;
}
</style>
<script>
export default {
data() {
return {
imageUrl: ''
};
},
methods: {
handleAvatarSuccess(res, file) {
this.imageUrl = URL.createObjectURL(file.raw);
},
beforeAvatarUpload(file) {
const isJPG = file.type === 'image/jpeg';
const isLt2M = file.size / 1024 / 1024 < 2;
if (!isJPG) {
this.$message.error('上传头像图片只能是 JPG 格式!');
}
if (!isLt2M) {
this.$message.error('上传头像图片大小不能超过 2MB!');
}
return isJPG && isLt2M;
}
}
}
</script>上述action是提交图片的地址，若需要穿参数可以使用el-upload的属性headers，然后就可以了，下面会拿到imageUrl，然后绑定在页面，显示在页面上，就完成了图片上传的功能。
二、利用H5上传图片
<template>
<div class="phone" for="upload" :class="{'card': useCategory === '3'}">
<input type="file" id="upload" accept="image/*" @change="openPhone" style="opacity:0;">
<img :src="headerImage" class="picture" alt="">
</div>
</template>
<script>
export default {
name: 'phone',
props: {
useCategory: '',
onThree: false,
isFlag: false
},
data() {
return {
icValue: '',
ocrResult: {},
headerImage: '',
}
},
methods: {
openPhone(e) {
if(!this.isFlag){
let files = e.target.files || e.dataTransfer.files
if (!files.length) return
this.picValue = files[0]
this.imgPreview(this.picValue)
}
},
imgPreview(file) {
let self = this
let Orientation
// 看支持不支持FileReader
if (!file || !window.FileReader) return
if (/^image/.test(file.type)) {
// 创建一个reader
let reader = new FileReader()
// 将图片2将转成 base64 格式
reader.readAsDataURL(file)
// 读取成功后的回调
reader.onloadend = function () {
let result = this.result
let img = new Image()
img.src = result
//判断图片是否大于100K,是就直接上传，反之压缩图片
if (this.result.length <= (1 * 1024)) {
self.headerImage = this.result
self.postImg(file)
} else {
img.onload = function () {
let data = self.compress(img, Orientation)
self.headerImage = data
let blob = self.dataURItoBlob(data)
self.postImg(blob)
}
}
}
}
},
postImg (file) {
//这里写接口
let formData = new FormData() // 创建form对象
formData.append('file', file) // 通过append向form对象添加数据
formData.append('useCategory', this.useCategory) // 如果还需要传替他参数的话
formData.append('platform', 'ewx') // 如果还需要传替他参数的话
this.$ajax({
headers: {
'Content-Type': 'multipart/form-data'
},
type: 'openPhone',
method: 'POST',
data: formData
}).then(res => {
console.log(res)
if( res.data.success) {
this.ocrResult = res.data.data.ocrResult
this.ocrResult.id = res.data.data.attach.id
this.ocrResult.url = res.data.data.attach.url
this.$emit('openPhone', this.ocrResult)
}else {
let msg
if(res.data.errExcep && res.data.errExcep != '') {
msg = res.data.errExcep
}else {
msg = res.data.errMsg
}
Toast({
message: msg,
duration: 2000
});
}
})
},
rotateImg (img, direction,canvas) {
//最小与最大旋转方向，图片旋转4次后回到原方向
const min_step = 0
const max_step = 3
if (img == null)return;
//img的高度和宽度不能在img元素隐藏后获取，否则会出错
let height = img.height
let width = img.width
let step = 2
if (step == null) {
step = min_step
}
if (direction == 'right') {
step++
//旋转到原位置，即超过最大值
step > max_step && (step = min_step)
} else {
step--;
step < min_step && (step = max_step)
}
//旋转角度以弧度值为参数
let degree = step * 90 * Math.PI / 180
let ctx = canvas.getContext('2d')
switch (step) {
case 0:
canvas.width = width
canvas.height = height
ctx.drawImage(img, 0, 0)
break
case 1:
canvas.width = height
canvas.height = width
ctx.rotate(degree)
ctx.drawImage(img, 0, -height)
break
case 2:
canvas.width = width
canvas.height = height
ctx.rotate(degree)
ctx.drawImage(img, -width, -height)
break
case 3:
canvas.width = height
canvas.height = width
ctx.rotate(degree)
ctx.drawImage(img, -width, 0)
break;
}
},
compress(img,Orientation) {
let canvas = document.createElement("canvas")
let ctx = canvas.getContext('2d')
//瓦片canvas
let tCanvas = document.createElement("canvas")
let tctx = tCanvas.getContext("2d")
let initSize = img.src.length
let width = img.width
let height = img.height
//如果图片大于四百万像素，计算压缩比并将大小压至400万以下
let ratio
if ((ratio = width * height / 4000000) > 1) {
console.log("大于400万像素")
ratio = Math.sqrt(ratio)
width /= ratio
height /= ratio
} else {
ratio = 1
}
canvas.width = width
canvas.height = height
// 铺底色
ctx.fillStyle = "#fff"
ctx.fillRect(0, 0, canvas.width, canvas.height)
//如果图片像素大于100万则使用瓦片绘制
let count
if ((count = width * height / 1000000) > 1) {
console.log("超过100W像素")
count = ~~(Math.sqrt(count) + 1) //计算要分成多少块瓦片
// 计算每块瓦片的宽和高
let nw = ~~(width / count)
let nh = ~~(height / count)
tCanvas.width = nw
tCanvas.height = nh
for (let i = 0; i < count; i++) {
for (let j = 0; j < count; j++) {
tctx.drawImage(img, i * nw * ratio, j * nh * ratio, nw * ratio, nh * ratio, 0, 0, nw, nh)
ctx.drawImage(tCanvas, i * nw, j * nh, nw, nh)
}
}
} else {
ctx.drawImage(img, 0, 0, width, height)
}
//修复ios上传图片的时候 被旋转的问题
if(Orientation != "" && Orientation != 1){
switch(Orientation){
case 6://需要顺时针（向左）90度旋转
this.rotateImg(img,'left',canvas)
break;
case 8://需要逆时针（向右）90度旋转
this.rotateImg(img,'right',canvas)
break;
case 3://需要180度旋转
this.rotateImg(img,'right',canvas) //转两次
this.rotateImg(img,'right',canvas);
break;
}
}
//进行最小压缩
let ndata = canvas.toDataURL('image/jpeg', 0.1);
console.log('压缩前：' + initSize);
console.log('压缩后：' + ndata.length);
console.log('压缩率：' + ~~(100 * (initSize - ndata.length) / initSize) + "%");
tCanvas.width = tCanvas.height = canvas.width = canvas.height = 0;
return ndata;
},
// base64转成bolb对象
dataURItoBlob(base64Data) {
var byteString;
if (base64Data.split(",")[0].indexOf("base64") >= 0)
byteString = atob(base64Data.split(",")[1]);
else byteString = unescape(base64Data.split(",")[1]);
var mimeString = base64Data
.split(",")[0]
.split(":")[1]
.split(";")[0];
var ia = new Uint8Array(byteString.length);
for (var i = 0; i < byteString.length; i++) {
ia[i] = byteString.charCodeAt(i);
}
return new Blob([ia], { type: mimeString });
}
}
}
</script>
<style lang="stylus" rel="stylesheet/stylus" scoped>
.phone-box
background #fff
overflow hidden
.info
border-top 1px solid #E0E0E0
background #fff
#upload
position absolute
top: 0
left 0
right 0
bottom 0
width: 100%;
height: 100%;
z-index 10
.picture
position absolute
top: 0
left 0
right 0
bottom 0
width: 100%;
height: 100%;
overflow: hidden;
background-position: center center;
background-repeat: no-repeat;
background-size: cover;
z-index 5
.phone
position relative
width 100%
height 3.26rem
font-size .3rem
background: #F3F5F7
.top-l
position absolute
top 0
left 0
width .625rem
height .625rem
background: url(../assets/images/top-l.png) no-repeat
background-size 100% 100%
z-index 10
.top-r
position absolute
top 0
right 0
width .625rem
height .625rem
background: url(../assets/images/top-r.png) no-repeat
background-size 100% 100%
z-index 10
.bottom-l
position absolute
bottom 0
left 0
width .625rem
height .625rem
background: url(../assets/images/bottom-l.png) no-repeat
background-size 100% 100%
z-index 10
.bottom-r
position absolute
bottom 0
right 0
width .625rem
height .625rem
background: url(../assets/images/bottom-r.png) no-repeat
background-size 100% 100%
z-index 10
.phone.card
width 100%
height 4.48rem
background: url(../assets/images/authentication-bg.png) no-repeat
background-size 100% 100%
.phone.wd-326
width 3.26rem
.input-call
border-bottom 1px solid #E0E0E0
padding .29rem .3rem
.tit
font-size .3rem
color #49505A
.no-phone
padding-top .76rem
.phone-icon
width .66rem
height .58rem
background url(../assets/images/phone.png) no-repeat
background-size 100% 100%
margin-bottom .32rem
.card .no-phone
padding-top 1.36rem
</style>