React tsx生成隨機(jī)驗(yàn)證碼

更新時(shí)間：2021年04月23日 17:14:15 作者：laipengfei19

這篇文章主要為大家詳細(xì)介紹了React tsx生成隨機(jī)驗(yàn)證碼，文中示例代碼介紹的非常詳細(xì)，具有一定的參考價(jià)值，感興趣的小伙伴們可以參考一下

React tsx 生成隨機(jī)驗(yàn)證碼，供大家參考，具體內(nèi)容如下

最近開(kāi)發(fā)React 使用tsx編寫(xiě)，沒(méi)有找到什么好的隨機(jī)生成驗(yàn)證碼的插件，自己就手?jǐn)]了一個(gè)，廢話不多話，直接上代碼。

tsx文件如下：

React代碼片.

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", //默認(rèn)canvas寬度
                height: "47", //默認(rèn)canvas高度
                type: "blend", //圖形驗(yàn)證碼默認(rèn)類(lèi)型blend:數(shù)字字母混合類(lèi)型、number:純數(shù)字、letter:純字母
                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);// 調(diào)用父組件傳入的函數(shù)，把自身賦給父組件
    }

    _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 = "您的瀏覽器版本不支持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") { //判斷驗(yàn)證碼類(lèi)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'; //隨機(jī)生成字體大小
            ctx.fillStyle = this.randomColor(50, 160); //隨機(jī)生成字體顏色       
            // ctx.fillStyle = "rgb(46, 137, 255)";//固定字體顏色
            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);
            /**設(shè)置旋轉(zhuǎn)角度和坐標(biāo)原點(diǎn)**/
            ctx.translate(x, y);
            ctx.rotate(deg * Math.PI / 180);
            ctx.fillText(txt, 0, 0);
            /**恢復(fù)旋轉(zhuǎn)角度和坐標(biāo)原點(diǎn)**/
            ctx.rotate(-deg * Math.PI / 180);
            ctx.translate(-x, -y);
        }
        /**繪制干擾線**/
        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;
        }
    }
    /**生成字母數(shù)組**/
    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(",");
    }
    /**生成一個(gè)隨機(jī)數(shù)**/
    randomNum(min, max) {
        return Math.floor(Math.random() * (max - min) + min);
    }
    /**生成一個(gè)隨機(jī)色**/
    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>
        )
    }
}

這里verifycode的樣式自己修改，一般代碼片.

import InputVerify from "../InputVerify"

這樣已經(jīng)能自動(dòng)生成驗(yàn)證碼了，如何進(jìn)行驗(yàn)證了，我這里也簡(jiǎn)單貼出來(lái)，這里Form用的antd，一看就懂

代碼片.

export default ($Child: any = {}) => {
 //Form提交的方法
 const onFinish = (values: any) => {
        if (values.vcode) {
            console.log($Child.validate(values.vcode))//調(diào)用子組件的方法驗(yàn)證
        }
    };
    
 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: '請(qǐng)輸入驗(yàn)證碼' }]}>
               <Input size="large" className="security-code" placeholder="請(qǐng)輸入驗(yàn)證碼" />
            </Form.Item>
   {/* 這里通過(guò)onRef來(lái)父組件調(diào)用子組件的方法 */}
   <InputVerify onRef={(ref) => { $Child = ref }}></InputVerify>
  </Form>
 )
}

上面這種寫(xiě)法呢確實(shí)是React老的寫(xiě)法，React16.8以后都用hook了，那我也改一下，代碼如下：

代碼片.

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, //默認(rèn)canvas寬度
                height: 47, //默認(rèn)canvas高度
                type: "blend", //圖形驗(yàn)證碼默認(rèn)類(lèi)型blend:數(shù)字字母混合類(lèi)型、number:純數(shù)字、letter:純字母
                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 = "您的瀏覽器版本不支持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") { //判斷驗(yàn)證碼類(lèi)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'; //隨機(jī)生成字體大小
            ctx.fillStyle = randomColor(50, 160); //隨機(jī)生成字體顏色       
            // ctx.fillStyle = "rgb(46, 137, 255)";//固定字體顏色
            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);
            /**設(shè)置旋轉(zhuǎn)角度和坐標(biāo)原點(diǎn)**/
            ctx.translate(x, y);
            ctx.rotate(deg * Math.PI / 180);
            ctx.fillText(txt, 0, 0);
            /**恢復(fù)旋轉(zhuǎn)角度和坐標(biāo)原點(diǎn)**/
            ctx.rotate(-deg * Math.PI / 180);
            ctx.translate(-x, -y);
        }
        /**繪制干擾線**/
        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();
        }
    }

        /**生成字母數(shù)組**/
    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(",");
    }
    /**生成一個(gè)隨機(jī)數(shù)**/
    function randomNum(min: any, max: any) {
        return Math.floor(Math.random() * (max - min) + min);
    }
    /**生成一個(gè)隨機(jī)色**/
    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>
    )
}

調(diào)用也簡(jiǎn)單，父組件聲明一個(gè)React.useRef，傳給子組件

const childRef = React.useRef<any>();
//這里code通過(guò)antD的Form表單的onFinish事件獲得
//調(diào)用子組件方法
childRef.current.validate(code)

<InputVerify cRef={childRef}></InputVerify>

好了，效果如下圖：