Maison >interface Web >tutoriel HTML >DIV内容垂直居中_html/css_WEB-ITnose
css垂直居中属性设置vertical-align: middle对div不起作用,例如:
1 <!DOCTYPE html> 2 <html lang="zh-CN"> 3 <head> 4 <meta charset="utf-8"> 5 <meta http-equiv="X-UA-Commpatible" content="IE=edge"> 6 <title>DIV垂直居中对齐</title> 7 <style type="text/css"> 8 * { 9 margin: 0;10 padding: 0;11 }12 13 html, body {14 width: 100%;15 height: 100%;16 }17 18 body {text-align: center; vertical-align: middle;}19 .outer {20 width: 400px;21 height: 120px;22 position: relative;23 left: 20px;24 top: 20px;25 text-align: center;26 vertical-align: middle;27 border: 1px dashed blue;28 }29 30 .button {31 width: 200px;32 height: 40px;33 }34 </style>35 </head>36 <body>37 <div class='outer'>38 <button class='button'>在DIV中垂直居中</button>39 </div>40 </body>41 </html>
运行后按钮没有在DIV中垂直居中:
解决思路:如果div和按钮的宽高都确定为具体像素值,可以直接设定按钮的css属性:position:relative; top为(div.height - button.height)/2,left为(div.width-button.height)/2;否则给按钮添加一个div父元素,宽高和按钮相 同,position设定为relative,top和left都为50%(即左上角位置设定在外层div的中心),再将按钮左上角位置坐标设定为父元素 div宽高(也等于按钮自身宽高)的-50%
详细代码如下:
1 <!DOCTYPE html> 2 <html lang="zh-CN"> 3 <head> 4 <meta charset="utf-8"> 5 <meta http-equiv="X-UA-Commpatible" content="IE=edge"> 6 <title>DIV垂直居中对齐</title> 7 <style type="text/css"> 8 * { 9 margin: 0;10 padding: 0;11 }12 13 html, body {14 width: 100%;15 height: 100%;16 }17 18 body {text-align: center; vertical-align: middle;}19 .outer {20 width: 400px;/* 或者为百分比 */21 height: 120px;22 position: relative;23 left: 20px;24 top: 20px;25 border: 1px dashed blue;26 }27 28 .inner {29 width: 200px;30 height: 40px;31 position: relative;32 position: relative;33 top: 50%;34 left: 50%;35 }36 37 .button {38 width: 200px;39 height: 40px;40 position: relative;41 top: -50%;42 left: -50%;43 }44 </style>45 </head>46 <body>47 <div class='outer'>48 <div class='inner'>49 <button class='button'>在DIV中垂直居中</button>50 </div>51 </div>52 </body>53 </html>
再次运行后,div中按钮上下居中显示
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