Javascript HTML5 Canvas_H5之家 - 中国HTML5教程资源分享第一站

Javascript HTML5 Canvas

suvllian 壺[ ] 2016-05-02

Javascript HTML5 Canvas,ο

HTML5 Canvasο

<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>DEMO6廭</title> </head> <body> <canvas> canvas  </canvas> <br/> <button>YELLOW</button> <button>RED</button> <button>BLUE</button> <button>GREEN</button> <button>WHITE</button> <button>BLACK</button> <br/> <button>4PX</button> <button>8PX</button> <button>16PX</button> <br/> <button>EXPORT</button> <br/> <img src=""> <br/> <script type="text/javascript"> var canvas = document.getElementById('canvas'); // var ctx = canvas.getContext("2d"); var fillStyle = "black"; ctx.fillRect(0,0,600,300); var onoff = false; //± var oldx = -10; var oldy = -10; // var linecolor = "white"; var linw = 4; canvas.addEventListener("mousemove",draw,true); // canvas.addEventListener("mousedown",down,false); // canvas.addEventListener("mouseup",up,false); // function down(event){ onoff = true; oldx = event.pageX - 10; oldy = event.pageY - 10; } function up(){ onoff = false; } function draw(event){ if (onoff==true) { var newx = event.pageX - 10; var newy = event.pageY - 10 ctx.beginPath(); ctx.moveTo(oldx,oldy); ctx.lineTo(newx,newy); ctx.strokeStyle = linecolor; ctx.lineWidth = linw; ctx.lineCap = "round"; ctx.stroke(); oldx = newx; oldy = newy; } } function copyimage(event) { var img_png_src = canvas.toDataURL("image/png"); //屣 document.getElementById("image_png").src = img_png_src; } </script> </body> </html>