<template>
<div class="s-canvas">
<!-- <canvas id="s-canvas" ></canvas> -->
<canvas ref="s-canvas" :width='contentWidth' :height='contentHeight' id="s-canvas" ></canvas>
</div>
</template>
<script>
export default{
name: 'SIdentify',
data () {
return {
}
},
props: {
identifyCode: {
type: String,
default: '1234'
},
fontSizeMin: {
type: Number,
default: 30
},
fontSizeMax: {
type: Number,
default: 35
},
backgroundColorMin: {
type: Number,
default: 180
},
backgroundColorMax: {
type: Number,
default: 240
},
colorMin: {
type: Number,
default: 50
},
colorMax: {
type: Number,
default: 160
},
lineColorMin: {
type: Number,
default: 40
},
lineColorMax: {
type: Number,
default: 180
},
dotColorMin: {
type: Number,
default: 0
},
dotColorMax: {
type: Number,
default: 255
},
contentWidth: {
type: Number,
default: 112
},
contentHeight: {
type: Number,
default: 38
}
},
methods: {
// 生成一个随机数
randomNum (min, max) {
return Math.floor(Math.random() * (max - min) + min)
},
// 生成一个随机的颜色
randomColor (min, max) {
let r = this.randomNum(min, max)
let g = this.randomNum(min, max)
let b = this.randomNum(min, max)
return 'rgb(' + r + ',' + g + ',' + b + ')'
},
drawPic () {
this.contentWidth = !this.contentWidth ? this.$refs.text.offsetWidth : this.contentWidth
this.contentHeight = !this.contentHeight ? this.$refs.text.offsetHeight : this.contentHeight
let canvas = document.getElementById('s-canvas')
let ctx = canvas.getContext('2d')
ctx.textBaseline = 'bottom'
// 绘制背景
ctx.fillStyle = this.randomColor(this.backgroundColorMin, this.backgroundColorMax)
ctx.fillRect(0, 0, this.contentWidth, this.contentHeight)
// 绘制文字
for (let i = 0; i < this.identifyCode.length; i++) {
this.drawText(ctx, this.identifyCode[i], i)
}
this.drawLine(ctx)
this.drawDot(ctx)
},
drawText (ctx, txt, i) {
ctx.fillStyle = this.randomColor(this.colorMin, this.colorMax)
ctx.font = this.randomNum(this.fontSizeMin, this.fontSizeMax) + 'px SimHei'
let x = (i + 1) * (this.contentWidth / (this.identifyCode.length + 1))
let y = this.randomNum(this.fontSizeMax, this.contentHeight - 5)
// var deg = this.randomNum(-45, 45)
// 修改坐标原点和旋转角度
ctx.translate(x, y)
// ctx.rotate(deg * Math.PI / 180)
ctx.fillText(txt, 0, 0)
// 恢复坐标原点和旋转角度
// ctx.rotate(-deg * Math.PI / 180)
ctx.translate(-x, -y)
},
drawLine (ctx) {
// 绘制干扰线
for (let i = 0; i < 2; i++) {
ctx.strokeStyle = this.randomColor(this.lineColorMin, this.lineColorMax)
ctx.beginPath()
ctx.moveTo(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight))
ctx.lineTo(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight))
ctx.stroke()
}
},
drawDot (ctx) {
// 绘制干扰点
for (let i = 0; i < 50; i++) {
ctx.fillStyle = this.randomColor(0, 255)
ctx.beginPath()
ctx.arc(this.randomNum(0, this.contentWidth), this.randomNum(0, this.contentHeight), 1, 0, 2 * Math.PI)
ctx.fill()
}
}
},
watch: {
identifyCode () {
this.drawPic()
}
},
mounted () {
this.drawPic()
}
}
</script>
<style lang="scss" scoped>
@import "../../style/mixin.scss";
#s-canvas{
width: pxTovw(120);
height: pxTovw(40);
}
</style>
