效果图：使用canvas组件对随机的数字字母添加插画背景、干扰线、干扰点
1、在components文件夹下新建securityCode.vue文件，代码：
<template>
<canvas id="s-canvas" :width="contentWidth" :height="contentHeight"></canvas>
</template>
<script>
export default {
name: "securityCode",
props: {
identifyCode: {
type: String,
default: "",
},
fontSizeMin: {
type: Number,
default: 22,
},
fontSizeMax: {
type: Number,
default: 40,
},
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: 120,
},
contentHeight: {
type: Number,
default: 40,
},
},
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() {
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) / 330);
ctx.fillText(txt, 0, 0);
// 恢复坐标原点和旋转角度
ctx.rotate((-deg * Math.PI) / 330);
ctx.translate(-x, -y);
},
drawLine(ctx) {
// 绘制干扰线
for (let i = 0; i < 3; 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 < 80; 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>
2、在登录页面引入并注册使用组件：
<el-form-item prop="pass" label="验证码" class="row" label-width="150px">
<div class="row space-between" style="width: 315px;">
<el-input type="text" style="width: 190px;" v-model="inputCode" autocomplete="off"></el-input>
<div @click="refreshCode()" style="line-height: 0;">
<!--验证码组件-->
<SecurityCode :identifyCode="identifyCode"></SecurityCode>
</div>
</div>
</el-form-item>
<el-form-item style="padding-left: 55px;">
<el-button type="primary" @click="submitForm()" icon="el-icon-s-custom">
<span style="font-size: 15px;letter-spacing: 10px;">登录</span>
</el-button>
</el-form-item>
<script>
//导入组件
import SecurityCode from "@/components/securityCode";
export default {
components: {
//注册
SecurityCode
},
data() {
identifyCode: "",//随机组合字符串
inputCode: "", //text框输入的验证码
},
mounted() {
this.refreshCode();
},
methods: {
//初始化验证码
refreshCode() {
this.inputCode = ''
this.identifyCode = ""; //输入框置空
this.makeCode(4); //验证码长度为4
},
//随机切换验证码
makeCode(length) {
let code = '';
for (let i = 0; i < length; i++) {
const r = Math.floor(Math.random() * 36);
if (r < 10) {
code += r;
} else {
code += String.fromCharCode(r - 10 + 65);
}
}
this.identifyCode = code
localStorage.setItem('code', code);
console.log(this.identifyCode);
},
submitForm(formName) {
const code = this.inputCode.toLowerCase();
const originalCode = localStorage.getItem('code').toLowerCase();
if (!code) {
this.$message.error('请输入验证码！');
return
} else if (code !== originalCode) {
this.$message.error('验证码输入错误！');
this.refreshCode()
return
}
// this.$api.Login({
// userName: this.ruleForm.user,
// password: this.ruleForm.pass,
// systemCode: null,
// }).then((data) => {
// })
},
}
}
</script>