JavaScript實現多球運動效果
阿新 • • 發佈:2020-09-08
本文例項為大家分享了JavaScript實現多球運動的具體程式碼,供大家參考,具體內容如下
程式碼如下:
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width,initial-scale=1.0"> <title>多球運動</title> <style> *{margin:0;padding:0;} body{background-color: #90f;} .ball{position: absolute;left:0;top:0;width:100px;height:100px;background: #f0f;border-radius: 50%;} </style> </head> <body> <script> run(22)//封裝 //定義速度 var speed; function run(num){ //創建出num個div for(var i=0;i<num;i++){ //[2,11) 隨機速度 speed = Math.floor(Math.random()*9+2); //建立生成節點 var div = document.createElement("div"); //新增類名 div.className = 'ball' //自定義屬性儲存值 div.speedX = Math.floor(Math.random()*9+2) div.speedY = Math.floor(Math.random()*9+2) //將div放置到body中 document.body.appendChild(div) } //獲取元素 var box = document.getElementsByClassName( "ball" ) //獲取文件可視區域的寬高 var maxX = document.documentElement.clientWidth - box[0].offsetWidth; var maxY = document.documentElement.clientHeight - box[0].offsetHeight; //自適應視窗 window.onresize = function(){ maxX = document.documentElement.clientWidth - box[0].offsetWidth; maxY = document.documentElement.clientHeight - box[0].offsetHeight; } play() function play(){ for(var i=0;i<num;i++){ //獲取 var ball = box[i]; var startTop = ball.offsetTop; var startLift = ball.offsetLeft; //startTop都為零; var top = startTop + ball.speedY; var left = startLift + ball.speedX; //判斷小球是否出左右邊界 if(left <= 0 || left >= maxX){ //改變方向 ball.speedX = -ball.speedX; ball.style.background=randomColor() //判斷 if(left <= 0){ left = 0; }else if(left >= maxX){ left = maxX; } } //判斷小球是否出上下邊界 if(top <= 0 || top >= maxY ){ // 改變方向; ball.speedY = -ball.speedY; ball.style.background=randomColor() //判斷 if( top <= 0 ){ top = 0; }else if( top >= maxY ){ top = maxY; } } ball.style.top = top + "px"; ball.style.left = left + "px"; } //執行動畫幀 requestAnimationFrame(play); } //顏色隨機 function randomColor() { var r = Math.floor(Math.random() * 256),g = Math.floor(Math.random() * 256),b = Math.floor(Math.random() * 256); return "rgb(" + r + "," + g + "," + b + ")"; } } </script> </body> </html>
以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支援我們。