canvas如何实现滑动验证-创新互联

小编给大家分享一下canvas如何实现滑动验证，相信大部分人都还不怎么了解，因此分享这篇文章给大家参考一下，希望大家阅读完这篇文章后大有收获，下面让我们一起去了解一下吧！

突然想到的方法，来试试吧

1.页面布局

样式

        *{
            margin: 0;
            padding: 0;
        }
        #canva{
                background: indianred;
        }

JS

    window.onload=function(){
        var canva=document.getElementById('canva');
        var ctx  =canva.getContext('2d');
        var h=canva.height;     
        var w=canva.width;
        var rext={                          //定义验证块的属性
            x:Math.random()*(w-50),
            y:Math.random()*(h-50),
        }
        var hk={                           //滑块属性
            x:'0',
            y:''
        }
        Rect();                            //绘制验证块
        Hk(0,rext.y);                      //绘制滑块

        canva.addEventListener('click',function(){
                var ev=ev||event;
                var x=ev.clientX;
                var y=ev.clientY;
                if(x>=0 && x<=50 && y>=rext.y && y<=rext.y+50  ){//canvas内部监听
                   canva.addEventListener('mousemove',function(ev){
                        ev=ev||event;
                        ctx.clearRect(hk.x,hk.y,50,50);   //清除滑块            
                        hk.x=ev.clientX;    
                        Hk(hk.x,rext.y);
                        //绘制滑块
                        var hk_x=ev.clientX;
                        var yz_x=rext.x;
                        (function(x,y){
                            if(x>y && x

以上是“canvas如何实现滑动验证”这篇文章的所有内容，感谢各位的阅读！相信大家都有了一定的了解，希望分享的内容对大家有所帮助，如果还想学习更多知识，欢迎关注创新互联行业资讯频道！