React tsx 生成随机验证码，供大家参考，具体内容如下
最近开发React 使用tsx编写，没有找到什么好的随机生成验证码的插件，自己就手撸了一个，废话不多话，直接上代码。
tsx文件如下：
React代码片.
import * as React from "react";
const size = 4;
const verifycode = {
width: "32%",
height: "32px",
marginLeft: "5%",
display:"inline-block",
position:"absolute" as "absolute",
top:"0",
right:"0",
}
export default class InputVerify extends React.Component<any, any> {
constructor(props) {
super(props);
this.state = {
options: {
id: "verifycode", //容器Id
canvasId: "verifyCanvas", //canvas的ID
width: "150", //默认canvas宽度
height: "47", //默认canvas高度
type: "blend", //图形验证码默认类型blend:数字字母混合类型、number:纯数字、letter:纯字母
code: "",
numArr: "0,1,2,3,4,5,6,7,8,9".split(","),
letterArr: this.getAllLetter(),
}
}
}
componentDidMount() {
const self = this;
setTimeout(() => {
self._init();
self.refresh();
}, 100)
this.props.onRef(this);// 调用父组件传入的函数，把自身赋给父组件
}
_init() {
let con = document.getElementById(this.state.options.id);
let canvas = document.createElement("canvas");
this.state.options.width = con.offsetWidth > 0 ? con.offsetWidth : "150";
this.state.options.height = con.offsetHeight > 0 ? con.offsetHeight : "47";
canvas.id = this.state.options.canvasId;
canvas.width = this.state.options.width;
canvas.height = this.state.options.height;
canvas.style.cursor = "pointer";
canvas.innerHTML = "您的浏览器版本不支持canvas";
con.appendChild(canvas);
let parent = this;
canvas.onclick = function () {
parent.refresh();
}
}
refresh() {
this.state.options.code = "";
let canvas : any = document.getElementById(this.state.options.canvasId);
let ctx = null;
if (canvas.getContext) {
ctx = canvas.getContext('2d');
} else {
return;
}
ctx.clearRect(0, 0, this.state.options.width, this.state.options.height);
ctx.textBaseline = "middle";
ctx.fillStyle = this.randomColor(180, 240);
ctx.fillStyle = "rgba(0,0,0,0)";//背景色
ctx.fillRect(0, 0, this.state.options.width, this.state.options.height);
if (this.state.options.type == "blend") { //判断验证码类型
var txtArr = this.state.options.numArr.concat(this.state.options.letterArr);
} else if (this.state.options.type == "number") {
var txtArr = this.state.options.numArr;
} else {
var txtArr = this.state.options.letterArr;
}
for (var i = 1; i <= size; i++) {
var txt = txtArr[this.randomNum(0, txtArr.length)];
this.state.options.code += txt;
ctx.font = this.randomNum(this.state.options.height / 2, this.state.options.height) + 'px SimHei'; //随机生成字体大小
ctx.fillStyle = this.randomColor(50, 160); //随机生成字体颜色
// ctx.fillStyle = "rgb(46, 137, 255)";//固定字体颜色
ctx.shadowOffsetX = this.randomNum(-3, 3);
ctx.shadowOffsetY = this.randomNum(-3, 3);
ctx.shadowBlur = this.randomNum(-3, 3);
ctx.shadowColor = "rgba(0, 0, 0, 0.3)";
var x = this.state.options.width / (size + 1) * i;
var y = this.state.options.height / 2;
var deg = this.randomNum(-30, 30);
ctx.translate(x, y);
ctx.rotate(deg * Math.PI / 180);
ctx.fillText(txt, 0, 0);
ctx.rotate(-deg * Math.PI / 180);
ctx.translate(-x, -y);
}
for (var i = 0; i < 4; i++) {
ctx.strokeStyle = this.randomColor(40, 180);
ctx.beginPath();
ctx.moveTo(this.randomNum(0, this.state.options.width), this.randomNum(0, this.state.options.height));
ctx.lineTo(this.randomNum(0, this.state.options.width), this.randomNum(0, this.state.options.height));
ctx.stroke();
}
}
validate(code) {
var code = code.toLowerCase();
var v_code = this.state.options.code.toLowerCase();
if (code == v_code) {
return true;
} else {
this.refresh();
return false;
}
}
getAllLetter() {
var letterStr = "a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z";
return letterStr.split(",");
}
randomNum(min, max) {
return Math.floor(Math.random() * (max - min) + min);
}
randomColor(min, max) {
var r = this.randomNum(min, max);
var g = this.randomNum(min, max);
var b = this.randomNum(min, max);
return "rgb(" + r + "," + g + "," + b + ")";
}
render() {
return (
<div id="verifycode" style={verifycode}></div>
)
}
}这里verifycode的样式自己修改，一般代码片.
import InputVerify from "../InputVerify"这样已经能自动生成验证码了，如何进行验证了，我这里也简单贴出来，这里Form用的antd，一看就懂
代码片.
export default ($Child: any = {}) => {
//Form提交的方法
const onFinish = (values: any) => {
if (values.vcode) {
console.log($Child.validate(values.vcode))//调用子组件的方法验证
}
};
const onFinishFailed = (errorInfo: any) => {
console.log('Failed:', errorInfo);
};
return (
<Form
{...layout}
name="basic"
onFinish={onFinish}
onFinishFailed={onFinishFailed}
>
<Form.Item name="vcode" rules={[{ required: true, message: '请输入验证码' }]}>
<Input size="large" className="security-code" placeholder="请输入验证码" />
</Form.Item>
{}
<InputVerify onRef={(ref) => { $Child = ref }}></InputVerify>
</Form>
)
}上面这种写法呢确实是React老的写法，React16.8以后都用hook了，那我也改一下，代码如下：
代码片.
import * as React from "react";
const size = 4;
const verifycode = {
width: "32%",
height: "32px",
marginLeft: "5%",
display:"inline-block",
position:"absolute" as "absolute",
top:"0",
right:"0",
}
export default ({cRef}) => {
const [code, setCode] = React.useState(Boolean);
const [options,setOptions] = React.useState({
id: "verifycode", //容器Id
canvasId: "verifyCanvas", //canvas的ID
width: 150, //默认canvas宽度
height: 47, //默认canvas高度
type: "blend", //图形验证码默认类型blend:数字字母混合类型、number:纯数字、letter:纯字母
code: "",
numArr: "0,1,2,3,4,5,6,7,8,9".split(","),
letterArr: getAllLetter(),});
React.useImperativeHandle(cRef,()=>({
validate : (vcode) => {
var vcode = vcode.toLowerCase();
var v_code = options.code.toLowerCase();
if (vcode == v_code) {
setCode(true);
} else {
refresh();
setCode(false);
}
return code;
}
}));
React.useEffect(()=>{
_init();
refresh();
})
function _init() {
let con = document.getElementById(options.id);
let canvas : any = document.createElement("canvas");
options.width = con.offsetWidth > 0 ? con.offsetWidth : 150;
options.height = con.offsetHeight > 0 ? con.offsetHeight : 47;
canvas.id = options.canvasId;
canvas.width = options.width;
canvas.height = options.height;
canvas.style.cursor = "pointer";
canvas.innerHTML = "您的浏览器版本不支持canvas";
con.appendChild(canvas);
canvas.onclick = function () {
refresh();
}
}
function refresh() {
options.code = "";
let canvas : any = document.getElementById(options.canvasId);
let ctx = null;
if (canvas.getContext) {
ctx = canvas.getContext('2d');
} else {
return;
}
ctx.clearRect(0, 0, options.width, options.height);
ctx.textBaseline = "middle";
ctx.fillStyle = randomColor(180, 240);
ctx.fillStyle = "rgba(0,0,0,0)";//背景色
ctx.fillRect(0, 0, options.width, options.height);
if (options.type == "blend") { //判断验证码类型
var txtArr = options.numArr.concat(options.letterArr);
} else if (options.type == "number") {
var txtArr = options.numArr;
} else {
var txtArr = options.letterArr;
}
for (var i = 1; i <= size; i++) {
var txt = txtArr[randomNum(0, txtArr.length)];
options.code += txt;
ctx.font = randomNum(options.height / 2, options.height) + 'px SimHei'; //随机生成字体大小
ctx.fillStyle = randomColor(50, 160); //随机生成字体颜色
// ctx.fillStyle = "rgb(46, 137, 255)";//固定字体颜色
ctx.shadowOffsetX = randomNum(-3, 3);
ctx.shadowOffsetY = randomNum(-3, 3);
ctx.shadowBlur = randomNum(-3, 3);
ctx.shadowColor = "rgba(0, 0, 0, 0.3)";
var x = options.width / (size + 1) * i;
var y = options.height / 2;
var deg = randomNum(-30, 30);
ctx.translate(x, y);
ctx.rotate(deg * Math.PI / 180);
ctx.fillText(txt, 0, 0);
ctx.rotate(-deg * Math.PI / 180);
ctx.translate(-x, -y);
}
for (var i = 0; i < 4; i++) {
ctx.strokeStyle = randomColor(40, 180);
ctx.beginPath();
ctx.moveTo(randomNum(0, options.width), randomNum(0, options.height));
ctx.lineTo(randomNum(0, options.width), randomNum(0, options.height));
ctx.stroke();
}
}
function getAllLetter() {
var letterStr = "a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z";
return letterStr.split(",");
}
function randomNum(min: any, max: any) {
return Math.floor(Math.random() * (max - min) + min);
}
function randomColor(min, max) {
var r = randomNum(min, max);
var g = randomNum(min, max);
var b = randomNum(min, max);
return "rgb(" + r + "," + g + "," + b + ")";
}
return (
<div id="verifycode" style={verifycode}></div>
)
}调用也简单，父组件声明一个React.useRef，传给子组件
const childRef = React.useRef<any>();
//这里code通过antD的Form表单的onFinish事件获得
//调用子组件方法
childRef.current.validate(code)
<InputVerify cRef={childRef}></InputVerify>好了，效果如下图：
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程网。
