js 实现简单文本编辑器

效果：

 

 代码：

 

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>简单文本编辑器</title>
    <style type="text/css">
        * {
            margin: 0;
            padding: 0;
        }

        html,
        body {
            width: 100%;
            height: 100%;
            margin: 0;
            padding: 0;
            font: 12px/1.5 tahoma, arial, 'hiragino sans gb', 'microsoft yahei', sans-serif;
            -webkit-font-smoothing: antialiased;
            overflow: hidden;
        }

        #mian {
            width: 640px;
            height: 100%;
        }

        #leftBox {
            background: #ecf0f5;
            width: 35px;
            height: 100%;
            text-align: left;
            float: left;
        }

        #test {
            border: 1px solid #eaeaea;
            outline: none;
            width: 600px;
            height: 100%;
            resize: none;
            background: rgb(250, 250, 250);
            line-height: 24px;
            font-size: 14px;
            float: left;
            padding: 10px 8px;
            color: black;
            font-family: inherit;
            box-sizing: border-box;
        }

        #leftNum {
            height: 100%;
            width: 100%;
            resize: none;
            outline: none;
            overflow-y: hidden;
            overflow-x: hidden;
            border: 0;
            background: rgb(247, 247, 247);
            color: #999;
            line-height: 24px;
            font-size: 14px;
            padding: 10px 4px;
            text-align: right;
            font-weight: bold;
            box-sizing: border-box;
        }
    </style>
</head>

<body>
    <div id="mian">
        <div id="leftBox"><textarea wrap="off" cols="2" id="leftNum" disabled></textarea>
        </div>
        <textarea id="test" name="content" onkeyup="keyUp()"
            onscroll="getId('leftNum').scrollTop = this.scrollTop;"></textarea>
    </div>
    <script type="text/javascript">
        var num = "";
        var test = getId('test');
        function getId(obj) {
            return document.getElementById(obj);
        }
        function keyUp() {
            var str = test.value;
            str = str.replace(/\r/gi, ""); // \r匹配一个回车符
            str = str.split("\n");
            n = str.length;
            line(n);
        }
        function line(n) {
            var lineobj = getId("leftNum");
            for (var i = 1; i <= n; i++) {
                if (document.all) {
                    num += i + "\r\n";// 判断浏览器是否是IE \n匹配一个换行符
                } else {
                    num += i + "\n";
                }
            }
            lineobj.value = num;
            num = "";
        }
    </script>
</body>

</html>
posted @ 2020-01-14 17:56  执手听风吟  阅读(579)  评论(0)    收藏  举报