JQuery canvas 验证码-白红宇

JQuery canvas 验证码

阅读量：5094 次

发布时间：2019-06-13

本文共 5091 字，大约阅读时间需要 16 分钟。

</div>

$(function(){

var show_num = [];

draw(show_num);

$("#canvas").on('click',function(){

draw(show_num);

})

$(".btn").on('click',function(){

var val = $(".input-val").val().toLowerCase();

//toLowerCase(); 把大写转换为小写，则验证码不分大小写

var num = show_num.join("");

if(val==''){

alert('请输入验证码！');

}else if(val == num){

alert('提交成功！');

$(".input-val").val('');

draw(show_num);

}else{

alert('验证码错误！请重新输入！');

$(".input-val").val('');

draw(show_num);

}

})

});

canvas的编辑：

function draw(show_num) {

var canvas_width=$('#canvas').width();

var canvas_height=$('#canvas').height();

var canvas = document.getElementById("canvas");//获取到canvas的对象，演员

var context = canvas.getContext("2d");//获取到canvas画图的环境，演员表演的舞台

canvas.width = canvas_width;

canvas.height = canvas_height;

var sCode = "A,B,C,E,F,G,H,J,K,L,M,N,P,Q,R,S,T,W,X,Y,Z,1,2,3,4,5,6,7,8,9,0";

var aCode = sCode.split(",");

var aLength = aCode.length;//获取到数组的长度

//验证码的个数在此处设置

for (var i = 0; i <= 3; i++) {

var j = Math.floor(Math.random() * aLength);//获取到随机的索引值

var deg = Math.random() * 30 * Math.PI / 180;//产生0~30之间的随机弧度

var txt = aCode[j];//得到随机的一个内容

show_num[i] = txt.toLowerCase();

var x = 10 + i * 20;//文字在canvas上的x坐标

var y = 20 + Math.random() * 8;//文字在canvas上的y坐标

context.font = "bold 23px 微软雅黑";

context.translate(x, y);

context.rotate(deg);

context.fillStyle = randomColor();

context.fillText(txt, 0, 0);

context.rotate(-deg);

context.translate(-x, -y);

}

// for (var i = 0; i <= 5; i++) { //验证码上显示线条

// context.strokeStyle = randomColor();

// context.beginPath();

// context.moveTo(Math.random() * canvas_width, Math.random() * canvas_height);

// context.lineTo(Math.random() * canvas_width, Math.random() * canvas_height);

// context.stroke();

// }

// for (var i = 0; i <= 30; i++) { //验证码上显示小点

// context.strokeStyle = randomColor();

// context.beginPath();

// var x = Math.random() * canvas_width;

// var y = Math.random() * canvas_height;

// context.moveTo(x, y);

// context.lineTo(x + 1, y + 1);

// context.stroke();

// }

}

function randomColor() {//得到随机的颜色值

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 + ")";

}

　　完整代码：

<!DOCTYPE html>

<html>

<head>

<title>canvas 验证码</title>

*{margin:0;padding:0;}

.code input{width:200px;height:25px;}

.code canvas{border:1px solid red;}

</style>

</head>

<body>

</div>

$(function () {

var show_num = [];

draw(show_num);

$("#canvas").on('click', function () {

draw(show_num);

})

$(".btn").on('click', function () {

var val = $(".input-val").val().toLowerCase();

//toLowerCase(); 把大写转换为小写，则验证码不分大小写

var num = show_num.join("");

if (val == '') {

alert('请输入验证码！');

} else if (val == num) {

alert('提交成功！');

$(".input-val").val('');

draw(show_num);

} else {

alert('验证码错误！请重新输入！');

$(".input-val").val('');

draw(show_num);

}

});

function draw(show_num) {

var canvas_width = $('#canvas').width();

var canvas_height = $('#canvas').height();

var canvas = document.getElementById("canvas"); //获取到canvas的对象，演员

var context = canvas.getContext("2d"); //获取到canvas画图的环境，演员表演的舞台

canvas.width = canvas_width;

canvas.height = canvas_height;

var sCode = "A,B,C,E,F,G,H,J,K,L,M,N,P,Q,R,S,T,W,X,Y,Z,1,2,3,4,5,6,7,8,9,0";

var aCode = sCode.split(",");

var aLength = aCode.length; //获取到数组的长度

//验证码的个数在此处设置

for (var i = 0; i <= 3; i++) {

var j = Math.floor(Math.random() * aLength); //获取到随机的索引值

var deg = Math.random() * 30 * Math.PI / 180; //产生0~30之间的随机弧度

var txt = aCode[j]; //得到随机的一个内容

show_num[i] = txt.toLowerCase();

var x = 10 + i * 20; //文字在canvas上的x坐标

var y = 20 + Math.random() * 8; //文字在canvas上的y坐标

context.font = "18px 微软雅黑";

context.translate(x, y);

context.rotate(deg);

context.fillStyle = randomColor();

context.fillText(txt, 0, 0);

context.rotate(-deg);

context.translate(-x, -y);

}

for (var i = 0; i <= 5; i++) { //验证码上显示线条

context.strokeStyle = randomColor();

context.beginPath();

context.moveTo(Math.random() * canvas_width, Math.random() * canvas_height);

context.lineTo(Math.random() * canvas_width, Math.random() * canvas_height);

context.stroke();

}

for (var i = 0; i <= 30; i++) { //验证码上显示小点

context.strokeStyle = randomColor();

context.beginPath();

var x = Math.random() * canvas_width;

var y = Math.random() * canvas_height;

context.moveTo(x, y);

context.lineTo(x + 1, y + 1);

context.stroke();

}

function randomColor() { //得到随机的颜色值

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 + ")";

}

});

</script>

</body>

</html>

转载于:https://www.cnblogs.com/duxingdexin/p/9180799.html

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