Javascript 如何使用html5在单击相应链接时用颜色填充圆圈
我试过这么多代码。我有两个圆圈,旁边有一个链接,我需要给相应链接的圆圈上色。提出一些解决方案Javascript 如何使用html5在单击相应链接时用颜色填充圆圈,javascript,jquery,html,html5-canvas,Javascript,Jquery,Html,Html5 Canvas,我试过这么多代码。我有两个圆圈,旁边有一个链接,我需要给相应链接的圆圈上色。提出一些解决方案 <body> <div class="row-fluid"> <div class="span1 offset3"> <canvas id="myCanvas" width="100" height="100"></canvas> </div> <
<body>
<div class="row-fluid">
<div class="span1 offset3">
<canvas id="myCanvas" width="100" height="100"></canvas>
</div>
<div class="span1">
<br/><a href="#" onclick="function();">Hello</a>
</div>
<div class="span1">
<canvas id="myCanvas1" width="100" height="100"></canvas>
</div>
<div class="span1">
<br/><a href="#" onclick="function();">Hi</a>
</div>
</div>
<script>
var c = document.getElementById("myCanvas");
var ctx = c.getContext("2d");
ctx.beginPath();
ctx.arc(55, 30, 20, 0, 2 * Math.PI);
ctx.stroke();
var c = document.getElementById("myCanvas1");
var ctx = c.getContext("2d");
ctx.beginPath();
ctx.arc(55, 30, 20, 0, 2 * Math.PI);
ctx.stroke();
function () {
//onclick function which will change the color of the correspondind circle
}
</script>
</body>
var c=document.getElementById(“myCanvas”);
var ctx=c.getContext(“2d”);
ctx.beginPath();
ctx.arc(55,30,20,0,2*Math.PI);
ctx.stroke();
var c=document.getElementById(“myCanvas1”);
var ctx=c.getContext(“2d”);
ctx.beginPath();
ctx.arc(55,30,20,0,2*Math.PI);
ctx.stroke();
函数(){
//onclick函数,该函数将更改相应的ind圆的颜色
}
为每个函数使用此代码脚本标记
<script>
var canvas = document.getElementById('myCanvas');
var context = canvas.getContext('2d');
var centerX = canvas.width / 2;
var centerY = canvas.height / 2;
var radius = 70;
context.beginPath();
context.arc(centerX, centerY, radius, 0, 2 * Math.PI, false);
context.fillStyle = 'blue';
context.fill();
context.lineWidth = 5;
context.strokeStyle = '#003300';
context.stroke();
</script>
var canvas=document.getElementById('myCanvas');
var context=canvas.getContext('2d');
var centerX=canvas.width/2;
var centerY=canvas.height/2;
var半径=70;
context.beginPath();
弧(centerX,centerY,半径,0,2*Math.PI,false);
context.fillStyle='blue';
context.fill();
context.lineWidth=5;
context.strokeStyle='#003300';
stroke();
单击html链接时如何填充画布圆圈
这是一个灵活的函数,它可以绘制一个圆,也可以选择填充该圆:
function drawCircle(context,fill){
context.beginPath();
context.arc(55, 30, 20, 0, 2 * Math.PI);
context.closePath();
context.stroke();
if(fill){
context.fill()
}
}
jquery可以监听锚上的点击
然后jquery调用fill=true的drawCircle函数(圆已填充)
下面是代码和小提琴:
正文{背景色:象牙色;填充:20px;}
画布{边框:1px纯红;}
$(函数(){
var canvas=document.getElementById(“myCanvas”);
var ctx=canvas.getContext(“2d”);
var canvas1=document.getElementById(“myCanvas1”);
var ctx1=canvas1.getContext(“2d”);
//画有笔划但没有填充的圆
画圈(ctx,假);
画圈(ctx1,假);
函数drawCircle(上下文、填充){
context.beginPath();
弧(55,30,20,0,2*Math.PI);
closePath();
stroke();
如果(填写){
context.fill()
}
}
//单击后填充圆圈
$(“#c1”)。单击(函数(){drawCircle(ctx,true);});
$(“#c2”)。单击(函数(){drawCircle(ctx1,true);});
}); // end$(函数(){});
// fill the circle on click
$("#c1").click(function(){ drawCircle(ctx,true); });
$("#c2").click(function(){ drawCircle(ctx1,true); });
<!doctype html>
<html>
<head>
<link rel="stylesheet" type="text/css" media="all" href="css/reset.css" /> <!-- reset css -->
<script type="text/javascript" src="http://code.jquery.com/jquery.min.js"></script>
<style>
body{ background-color: ivory; padding:20px; }
canvas{border:1px solid red;}
</style>
<script>
$(function(){
var canvas=document.getElementById("myCanvas");
var ctx=canvas.getContext("2d");
var canvas1=document.getElementById("myCanvas1");
var ctx1=canvas1.getContext("2d");
// draw stroked but not filled circles
drawCircle(ctx,false);
drawCircle(ctx1,false);
function drawCircle(context,fill){
context.beginPath();
context.arc(55, 30, 20, 0, 2 * Math.PI);
context.closePath();
context.stroke();
if(fill){
context.fill()
}
}
// fill the circle on click
$("#c1").click(function(){ drawCircle(ctx,true); });
$("#c2").click(function(){ drawCircle(ctx1,true); });
}); // end $(function(){});
</script>
</head>
<body>
<div class="row-fluid">
<div class="span1 offset3">
<canvas id="myCanvas" width="100" height="100"></canvas>
</div>
<div class="span1">
<br/><a id="c1" href="#">Hello</a>
</div>
<div class="span1">
<canvas id="myCanvas1" width="100" height="100"></canvas>
</div>
<div class="span1">
<br/><a id="c2" href="#">Hi</a>
</div>
</div>
</body>
</html>