随手写了个简单的碰撞检测的代码。检测box1和box2是否发生碰撞，若发生碰撞，box2颜色发生随机改变，并反弹到随机位置。
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> <style> .box1,.box2{ width: 100px; height: 100px; background-color: #f00; position:absolute; } .box2{ background-color: #00f; left: 200px; top: 200px; } </style> </head> <body> <div></div> <div></div> </body> <script> var box1=document.querySelector(".box1"); var box2=document.querySelector(".box2"); box1.addEventListener("mousedown",mouseHandler); function mouseHandler(e){ if(e.type==="mousedown"){ e.preventDefault(); document.elem=this; document.pointX= e.offsetX; document.pointY= e.offsetY; document.addEventListener("mousemove",mouseHandler); this.addEventListener("mouseup",mouseHandler); }else if(e.type==="mousemove"){ this.elem.style.left= e.x-this.pointX+"px"; this.elem.style.top= e.y-this.pointY+"px"; hitText(this.elem,box2); }else if(e.type==="mouseup"){ document.removeEventListener("mousemove",mouseHandler); this.removeEventListener("mouseup",mouseHandler); } } function hitText(elem1,elem2){ var rect1=elem1.getBoundingClientRect(); var rect2=elem2.getBoundingClientRect(); var ponit1={x:rect1.x,y:rect1.y}; var ponit4={x:rect1.x+rect1.width,y:rect1.y+rect1.height}; if( ponit4.x>rect2.x &&ponit1.x<(rect2.x+rect2.width) &&ponit4.y>rect2.y &&ponit1.y<(rect2.y+rect2.height)){ elem2.style.backgroundColor=randomColor(); elem2.style.left=Math.round(Math.random()*document.documentElement.clientWidth)+"px"; elem2.style.top=Math.round(Math.random()*document.documentElement.clientHeight)+"px"; } } function randomColor(){ var a=Math.round(Math.random()*255); var b=Math.round(Math.random()*255); var c=Math.round(Math.random()*255); var color="rgb("+ a+","+b+","+c+")"; return color; } </script> </html>