js to implement verification code interference (static)
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This article shares the specific code of js to implement verification code interference for your reference. The specific content is as follows Effect
Code
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style>
*{
padding: 0;
margin: 0;
}
canvas{
background: #272822;
}
</style>
</head>
<body>
<canvas id='canvas' width='800' height='500'></canvas>
<script>
//Get the drawing board var canvas=document.getElementById('canvas');
//Get the drawing environment var cv=canvas.getContext('2d');
cv.fillStyle = '#272822';
cv2.fillRect(0,0,800,500);
cv.font='80px Microsoft YaHei';
cv2.fillStyle='greenyellow';
cv2.fillText( Math.floor(Math.random()*10000),200,200);
//Get all image pixel information var alldata=cv.getImageData(0,0,800,500);
//Get the number of pixels var dian=alldata.data.length/4;
for(var i=0;i<10000;i++){
//Get a random number var num=Math.floor(Math.random()*dian);
//Calculate the starting number of the four pieces of information corresponding to the pixel var start=(num-1)*4;
alldata.data[start]=Math.floor(Math.random()*256);
alldata.data[start+1]=Math.floor(Math.random()*256);
alldata.data[start+2]=Math.floor(Math.random()*256);
}
//Write the data back to the drawing board cv.putImageData(alldata,0,0);
</script>
</body>
</html>The above is the full content of this article. I hope it will be helpful for everyone’s study. I also hope that everyone will support 123WORDPRESS.COM. You may also be interested in:
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