怎樣調整可以不閃？canvas能根據內容調整大小么？怎樣設置可以在重新輸入之后點擊go是重新畫圖，而不是現在這樣的疊加？<!DOCTYPE?html?PUBLIC?"-//W3C//DTD?XHTML?1.0?Transitional//EN"?"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html?xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta?http-equiv="Content-Type"?content="text/html;?charset=utf-8"?/>
<title>基本循環</title>
<script?type="text/javascript">
function?block(){
????var?h?=?document.myForm.txtCount.value;
????
????var?c?=?document.getElementById("myCanvas");
????var?cxt?=?c.getContext("2d");
?????for(i?=?0;?i?<=?h;?i++){
????????cxt.fillStyle="#FF0000";
????????cxt.fillRect(0,0+i*100,150,75);
????????
????????cxt.fillStyle="#ffffff";
????????cxt.beginPath();
????????cxt.arc(70,15+i*100,10,0,Math.PI*2,true);
????????cxt.closePath();
????????cxt.fill();
????}
}
</script>
</head>
<body>
<form?name?=?"myForm">
????<input?type="text"?name="txtCount"/>
????<input?type="submit"?name?=?"Submit"?value="Go!"?onclick="block()"/>
</form>
<canvas?id="myCanvas"?width="400"??height=4000?style="border:1px?solid?#c3c3c3;">Your?browser?does?not?support?the?canvas?element.</canvas>
</body>
</html>謝謝各位大神了！??！
關于js在canvas中畫圖：為什么在瀏覽器中運行閃一下就沒有了，canvas能根據畫布中的東西調整大小么
qq_伽利略扭秤_0
2017-04-19 14:38:02