固定容器内任意个div填充算法

<!DOCTYPE html>
<html>
 
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <title> </title>
    <style>
        #box{
            height: 600px;
            width: 600px;
            border: 1px solid black;
        }
        </style>
</head>
 
<body>
    <input id="sr" />
    <input type="button" id="bt" value="自动生成div" />
    <div id="box"></div>
</body>
<script>
    window.onload = function () {
        var aBtn = document.getElementById('bt');
        var oBox = document.getElementById('box');
        var oSr = document.getElementById('sr');
        var str = '';
        var num = 0;
        var flag = 0;
        var aColor = ['red', 'blue', 'green', 'yellow', 'purple', 'pink', 'gray'];
        //自动生成100个10*10的div
        aBtn.onclick = function () {
            str = '';
            num = oSr.value;  //3
            cnum = Math.round(Math.sqrt(num));  //2
            lnum = Math.floor(num / cnum);  //1
            xnum = 0;
            if(num != 3){
                for (var i = 0; i < lnum; i++) {
                    for (var j = 0; j < cnum + xnum; j++) {  
                        if (i == lnum - 1) {
                            xnum = num - cnum * lnum;
                        }
                        str += '<div style = "float:left;width:' + Math.floor(oBox.clientWidth / (cnum + xnum)) + 'px;height:' + Math.floor(oBox.clientHeight / lnum) + 'px;background:' + aColor[(i + j) % aColor.length] + ';"></div>';
                    }
                    str += '<br />';
                }
            }else{
                for (var i = 0; i < cnum; i++) {
                    for (var j = 0; j < lnum + xnum; j++) {  
                        if (i == cnum - 1) {
                            xnum = num - cnum * lnum;
                        }
                        str += '<div style = "float:left;width:' + Math.floor(oBox.clientWidth / (lnum + xnum)) + 'px;height:' + Math.floor(oBox.clientHeight / cnum) + 'px;background:' + aColor[(i + j) % aColor.length] + ';"></div>';
                    }
                    str += '<br />';
                }
            }
            
            oBox.innerHTML = str;
        }
    }
</script>
 
</html>

效果如下:

posted @ 2019-01-30 11:13  枫叶布  阅读(320)  评论(0编辑  收藏  举报