日期:2014-05-17 浏览次数:20700 次
主要包含两部分,一是网页,在网页中添加一个canvas标签,主要的部分还是使用javascript实现对画布的控制
html部分
<!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> <title> 网页时钟 </title> <meta http-equiv="Content-Type" content="text/html;charset=utf-8" /> <meta name="description" content="" /> <script language="JavaScript" type = "text/javascript" src = "drawImage.js"></script> <script type="text/css"> div#btn { margin-top:300px;} </script> </head> <body > <div id = "btn"> <Button onclick = "drawImage()">单击画图</Button> <Button onclick = "second_pointer_move()">秒针移动</Button> <Button onclick = "demo()">示例</Button> </div> <canvas id="mycanvas" width='200' height='200' style="border:1px solid #c3c3c3;" >浏览器不支持</canvas> </body> </html>
js部分
setInterval('second_pointer_move()',1000); setInterval('minute_pointer_move()',1000); setInterval('hour_pointer_move()',1000); //初始化图形 var arr_loc = [100,100,100,100,100,100]; function drawImage(){ var can_vas = document.getElementById("mycanvas"); var ctx = can_vas.getContext("2d"); ctx.fillStyle='#c3c33c'; ctx.strokeStyle='#00ff00'; ctx.beginPath(); // Start the path ctx.arc(100, 100, 100, 0, Math.PI*2,true); // Draw a circle ctx.closePath(); ctx.fill(); ctx.stroke(); add_text(); } function add_text(){ var can_vas = document.getElementById("mycanvas"); var ctx = can_vas.getContext("2d"); ctx.save(); ctx.textAlign ='center'; ctx.font = "15px impact"; ctx.fillStyle='#ff0000'; ctx.fillText("12",100,20,100); ctx.fillText("6",100,195,100); ctx.fillText("3",190,105,100); ctx.fillText("9",8,105,100); } function cover_pointer(arr_loc_x,arr_loc_y){ var can_vas = document.getElementById("mycanvas"); var ctx = can_vas.getContext("2d"); ctx.beginPath(); ctx.moveTo(100,100); ctx.lineWidth = 2; ctx.strokeStyle='#c3c33c'; ctx.lineTo(arr_loc_x,arr_loc_y); ctx.closePath(); ctx.stroke(); } //秒针移动 function second_pointer_move(){ cover_pointer(arr_loc[0],arr_loc[1]); //drawImage(); var time = new Date(); var second_count = time.getSeconds(); var length = 80; var second_pointer_x ; var second_pointer_y ; var can_vas = document.getElementById("mycanvas"); var ctx = can_vas.getContext("2d"); angle = second_count*6; angle_sin = Math.sin(angle*Math.PI/180); angle_cos = Math.cos(angle*Math.PI/180); //计算终点坐标 switch(Math.floor(angle/90)){ case 0 : { second_pointer_x = 100 + length*angle_sin; second_pointer_y = 100 - length*angle_cos; break; } case 1: { second_pointer_x = 100 + length*angle_sin; second_pointer_y = 100 - length*angle_cos; break; } case 2: { second_pointer_x = 100 + length*angle_sin; second_pointer_y = 100 - length*angle_cos; break; } default : { second_pointer_x = 100 + length*angle_sin; second_pointer_y = 100 - length*angle_cos; } } arr_loc[0] = second_pointer_x; arr_loc[1] = second_pointer_y; ctx.beginPath(); ctx.moveTo(100,100); ctx.lineWidth = 1; ctx.strokeStyle="#00ff00"; ctx.lineTo(second_pointer_x,second_pointer_y); ctx.closePath(); ctx.stroke(); } //分针移动 function minute_pointer_move(){ cover_pointer(arr_loc[2],arr_loc[3]); //drawImage(); var time = new Date(); var second_count = time.getMinutes(); var length = 65; var sec