我不需要它在您键入时自动调整大小，我只需要在页面加载变量时它是正确的大小$row['text'];
<textarea style="width:630px;"><? echo $row['text']; ?></textarea>
因此，当页面加载时，textarea 将显示该文本的值。我试图让它计算行数并根据它设置文本区域的高度
问问题
2230 次
4 回答
3
于 2012-08-02T01:33:20.413 回答
1
function set_height($str) {
$ary = explode("\n", $str);
$style = '';
if(is_array($ary) && count($ary)>1) {
$height = 18 * count($ary);
$style=' style="height:'.$height.'px; width:630px;" ';
}
return $style;
}
文本区域
<textarea <?=set_height($row['text']);?> ><? echo $row['text'];?></textarea>
于 2012-08-02T01:36:15.080 回答
1
Jquery autoresize 是最好的选择。我认为可行的唯一其他选项是使用文本“rows”和“cols”属性。测量将等于大约 630 像素、大约 32 的列数（基于 630/20 20 是平均字符宽度）。然后，您只需要知道需要多少行，这是一个更简单的方程式。
//Divide the width by the height to get the number of rows required, then round up with
//math.ceil to get a rounded number. (1.01 rows would still need to be 2 rows)
$num_rows = math.ceil(32 / strlen($rows['text']));
<textarea rows="<? echo $num_rows ?>" cols="32"><? echo $row['text']; ?></textarea>
于 2012-08-02T02:07:21.940 回答
0
只需将高度设置为等于字符数，就像这样......我还添加了 respensive 选项
<?php
function set_px_height($var) {
$px = strlen($var);
$style = '';
$height = $px;
if (!ismovil()){
$height = $height / 4;
}else{
$height = $height * 0.80;
}
if ($height < 40){
$height = 50;
}
$style=' style="height:'.$height.'px;"';
return $style;
}
function ismovil(){
$useragent=$_SERVER['HTTP_USER_AGENT'];
if(preg_match('/(android|bb\d+|meego).+mobile|avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows (ce|phone)|xda|xiino/i',$useragent)||preg_match('/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|yas\-|your|zeto|zte\-/i',substr($useragent,0,4))){
return true ;
}
}?>
像这样在 textarea
<textarea <?=set_px_height($row['text']);?> ><? echo $row['text'];?></textarea>
于 2020-04-04T19:33:19.140 回答