H5+JS生成验证码

效果图如下:

 

<canvas id="canvas1"  style="margin-left: 200px;"></canvas><br />
<button id="btnRefresh" style="position: relative;left: 200px;">看不清,刷新一下</button>

<script>
    /*定义函数生成随机颜色*/
    function colorRandom(){
        var r = Math.floor(Math.random()*256);
        var g = Math.floor(Math.random()*256);
        var b = Math.floor(Math.random()*256);
        return "rgb("+ r + ","+ g +","+ b+")";
    }

    /*生成随机数*/
    var canvas,context;
    function getYZ(){
        canvas = document.getElementById("canvas1");
        context = canvas.getContext('2d');
        canvas.width = 200;
        canvas.height = 100;
        context.beginPath();
        context.fillStyle = colorRandom();//显示验证码区域的背景色
        context.rect(0,55,100,40);
        context.fill();
        for(var i = 0;i<4;i++){
            context.font =( Math.random()*20+16)+"px 微软雅黑";//数字随机大小
            context.fillStyle = colorRandom();//数字颜色
            context.fillText(parseInt(Math.random()*9), 20*i,90);   //0-9的随机数
        }
    }

    /*实现*/
    window.onload = function(){
        getYZ();
        document.getElementById("btnRefresh").onclick = function(){
            getYZ();
        }
    }
</script>


<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>图形验证码</title>
</head>
<body>
<div id="v_container" style="width: 200px;height: 50px;"></div>
<input type="text" id="code_input" value="" placeholder="请输入验证码"/><button id="my_button">验证</button>
</body>
<script>
    !(function(window, document) {
        function GVerify(options) { //创建一个图形验证码对象,接收options对象为参数
            this.options = { //默认options参数值
                id: "", //容器Id
                canvasId: "verifyCanvas", //canvas的ID
                width: "100", //默认canvas宽度
                height: "30", //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: ""
            }

            if(Object.prototype.toString.call(options) == "[object Object]"){//判断传入参数类型
                for(var i in options) { //根据传入的参数,修改默认参数值
                    this.options[i] = options[i];
                }
            }else{
                this.options.id = options;
            }

            this.options.numArr = "0,1,2,3,4,5,6,7,8,9".split(",");
            this.options.letterArr = getAllLetter();

            this._init();
            this.refresh();
        }

        GVerify.prototype = {
            /**版本号**/
            version: '1.0.0',

            /**初始化方法**/
            _init: function() {
                var con = document.getElementById(this.options.id);
                var canvas = document.createElement("canvas");
                this.options.width = con.offsetWidth > 0 ? con.offsetWidth : "100";
                this.options.height = con.offsetHeight > 0 ? con.offsetHeight : "30";
                canvas.id = this.options.canvasId;
                canvas.width = this.options.width;
                canvas.height = this.options.height;
                canvas.style.cursor = "pointer";
                canvas.innerHTML = "您的浏览器版本不支持canvas";
                con.appendChild(canvas);
                var parent = this;
                canvas.onclick = function(){
                    parent.refresh();
                }
            },

            /**生成验证码**/
            refresh: function() {
                this.options.code = "";
                var canvas = document.getElementById(this.options.canvasId);
                if(canvas.getContext) {
                    var ctx = canvas.getContext('2d');
                }else{
                    return;
                }

                ctx.textBaseline = "middle";

                ctx.fillStyle = randomColor(180, 240);
                ctx.fillRect(0, 0, this.options.width, this.options.height);

                if(this.options.type == "blend") { //判断验证码类型
                    var txtArr = this.options.numArr.concat(this.options.letterArr);
                } else if(this.options.type == "number") {
                    var txtArr = this.options.numArr;
                } else {
                    var txtArr = this.options.letterArr;
                }

                for(var i = 1; i <= 4; i++) {
                    var txt = txtArr[randomNum(0, txtArr.length)];
                    this.options.code += txt;
                    ctx.font = randomNum(this.options.height/2, this.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.shadowOffsetX = randomNum(-3, 3);
                    ctx.shadowOffsetY = randomNum(-3, 3);
                    ctx.shadowBlur = randomNum(-3, 3);
                    ctx.shadowColor = "rgba(0, 0, 0, 0.3)";
                    var x = this.options.width / 5 * i;
                    var y = this.options.height / 2;
                    var deg = randomNum(-30, 30);
                    /**设置旋转角度和坐标原点**/
                    ctx.translate(x, y);
                    ctx.rotate(deg * Math.PI / 180);
                    ctx.fillText(txt, 0, 0);
                    /**恢复旋转角度和坐标原点**/
                    ctx.rotate(-deg * Math.PI / 180);
                    ctx.translate(-x, -y);
                }
                /**绘制干扰线**/
                for(var i = 0; i < 4; i++) {
                    ctx.strokeStyle = randomColor(40, 180);
                    ctx.beginPath();
                    ctx.moveTo(randomNum(0, this.options.width), randomNum(0, this.options.height));
                    ctx.lineTo(randomNum(0, this.options.width), randomNum(0, this.options.height));
                    ctx.stroke();
                }
                /**绘制干扰点**/
                for(var i = 0; i < this.options.width/4; i++) {
                    ctx.fillStyle = randomColor(0, 255);
                    ctx.beginPath();
                    ctx.arc(randomNum(0, this.options.width), randomNum(0, this.options.height), 1, 0, 2 * Math.PI);
                    ctx.fill();
                }
            },

            /**验证验证码**/
            validate: function(code){
                var code = code.toLowerCase();
                var v_code = this.options.code.toLowerCase();
                console.log(v_code);
                if(code == v_code){
                    return true;
                }else{
                    this.refresh();
                    return false;
                }
            }
        }
        /**生成字母数组**/
        function getAllLetter() {
            var letterStr = "a,b,c,d,e,f,g,h,i,j,k,l,m,n,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(",");
        }
        /**生成一个随机数**/
        function randomNum(min, max) {
            return Math.floor(Math.random() * (max - min) + min);
        }
        /**生成一个随机色**/
        function randomColor(min, max) {
            var r = randomNum(min, max);
            var g = randomNum(min, max);
            var b = randomNum(min, max);
            return "rgb(" + r + "," + g + "," + b + ")";
        }
        window.GVerify = GVerify;
    })(window, document);
</script>
<script>
    var verifyCode = new GVerify("v_container");

    document.getElementById("my_button").onclick = function(){
        var res = verifyCode.validate(document.getElementById("code_input").value);
        if(res){
            alert("验证正确");
        }else{
            alert("验证码错误");
        }
    }
</script>
</html>

 

posted @ 2018-06-26 16:13  一个人的孤独自白  阅读(3162)  评论(0编辑  收藏  举报