• 用键盘控制DIV && Div闪烁


    <!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>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>用键盘控制DIV</title>
    <style type="text/css">
    html,body{overflow:hidden;}
    body{margin:0;padding:0;}
    pre{color:green;padding:10px 15px;background:#f0f0f0;border:1px dotted #333;font:12px/1.5 Courier New;margin:12px;}
    span{color:#999;}
    #box{position:absolute;top:50px;left:300px;100px;height:100px;background:red;}
    </style>
    <script type="text/javascript">
    window.onload = function ()
    {
        var oBox = document.getElementById("box");
        var bLeft = bTop = bRight = bBottom = bCtrlKey = false;
        
        setInterval(function ()
        {
            if (bLeft)
            {
                oBox.style.left = oBox.offsetLeft - 10 + "px"
            }
            else if (bRight)
            {
                oBox.style.left = oBox.offsetLeft + 10 + "px"
            }
            
            if (bTop)
            {
                oBox.style.top = oBox.offsetTop - 10 + "px"    
            }
            else if(bBottom)
            {
                oBox.style.top = oBox.offsetTop + 10 + "px"
            }
            //防止溢出
            limit();
        },30);    
        
        document.onkeydown = function (event)
        {
            var event = event || window.event;
            bCtrlKey = event.ctrlKey;
            
            switch (event.keyCode)
            {
                case 37:
                    bLeft = true;
                    break;
                case 38:
                    if(bCtrlKey)
                    {
                        var oldWidth = oBox.offsetWidth;
                        var oldHeight = oBox.offsetHeight;
                        
                        oBox.style.width = oBox.offsetWidth * 1.5 + "px";
                        oBox.style.height = oBox.offsetHeight * 1.5 + "px";                
                        
                        oBox.style.left = oBox.offsetLeft - (oBox.offsetWidth - oldWidth) / 2 + "px";
                        oBox.style.top = oBox.offsetTop - (oBox.offsetHeight - oldHeight) / 2 + "px";
                        
                        break;    
                    }
                    bTop = true;
                    break;
                case 39:
                    bRight = true;
                    break;
                case 40:
                    if(bCtrlKey)
                    {
                        var oldWidth = oBox.offsetWidth;
                        var oldHeight = oBox.offsetHeight;
                        
                        oBox.style.width = oBox.offsetWidth * 0.75 + "px";
                        oBox.style.height = oBox.offsetHeight * 0.75 + "px";                
                        
                        oBox.style.left = oBox.offsetLeft - (oBox.offsetWidth - oldWidth) / 2 + "px";
                        oBox.style.top = oBox.offsetTop - (oBox.offsetHeight - oldHeight) / 2 + "px";
                        
                        break;    
                    }
                    bBottom = true;
                    break;
                case 49:
                    bCtrlKey && (oBox.style.background = "green");
                    break;
                case 50:
                    bCtrlKey && (oBox.style.background = "yellow");
                    break;
                case 51:
                    bCtrlKey && (oBox.style.background = "blue");
                    break;
            }
            
            return false
        };
    
        document.onkeyup = function (event)
        {
            switch ((event || window.event).keyCode)
            {
                case 37:
                    bLeft = false;
                    break;
                case 38:
                    bTop = false;
                    break;
                case 39:
                    bRight = false;
                    break;
                case 40:
                    bBottom = false;
                    break;
            }
        };
    
        //防止溢出
        function limit()
        {
            var doc = [document.documentElement.clientWidth, document.documentElement.clientHeight]
            //防止左侧溢出
            oBox.offsetLeft <=0 && (oBox.style.left = 0);
            //防止顶部溢出
            oBox.offsetTop <=0 && (oBox.style.top = 0);
            //防止右侧溢出
            doc[0] - oBox.offsetLeft - oBox.offsetWidth <= 0 && (oBox.style.left = doc[0] - oBox.offsetWidth + "px");
            //防止底部溢出
            doc[1] - oBox.offsetTop - oBox.offsetHeight <= 0 && (oBox.style.top = doc[1] - oBox.offsetHeight + "px")
        }
    };
    </script>
    </head>
    <body>
    <pre>
    红色方块为键盘操作区域,您可以进行如下操作:
    
    上:↑ 下:↓ 左:← 右:→
    
    Ctrl + 1 : 背景变为绿色
    Ctrl + 2 : 背景变为黄色
    Ctrl + 3 : 背景变为蓝色
    Ctrl + ↑ : 放大
    Ctrl + ↓ : 缩小
    </pre>
    <div id="box"></div>
    </body>
    </html>
    Div闪烁
    <!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>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>Div闪烁</title>
    <style type="text/css">
    #box{position:absolute;top:50%;left:50%;color:#fff;200px;height:200px;background:red;cursor:pointer;letter-spacing:5px;text-align:center;font:12px/200px Arial;margin:-100px 0 0 -100px;}
    </style>
    <script type="text/javascript">
    window.onload = function ()
    {
        var oBox = document.getElementById("box");
        var timer = null;        
        
        oBox.onclick = function ()
        {            
            var i = 0;    
            clearInterval(timer);
            timer = setInterval(function () {
                oBox.style.display = i++ % 2 ? "none" : "block";
                i > 6 && (clearInterval(timer))
            }, 80)
        }
    };
    </script>
    </head>
    <body>
    <div id="box">点击我就闪</div>
    </body>
    </html>
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  • 原文地址:https://www.cnblogs.com/mayufo/p/4475032.html
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