php substr截断汉字乱码解决办法

<?php
echo substr("Hello world!",6);
?>

输出：

world!

echo substr('中国文',1);

<?php
$str = '这样一来我的字符串就不会有乱码^_^';

echo "mb_substr:" . mb_substr($str, 0, 7, 'utf-8');
//结果：这样一来我的字
echo "<br>";

echo "mb_strcut:" . mb_strcut($str, 0, 6, 'utf-8');
//结果：这样
?>

function msubstr($str, $start, $len) {
  $tmpstr = "";
  $strlen = $start + $len;
  for($i = 0; $i < $strlen; $i++) {
   if(ord(substr($str, $i, 1)) > 0xa0) {
    $tmpstr .= substr($str, $i, 2);
    $i++;
   } else
    $tmpstr .= substr($str, $i, 1);
  }
  return $tmpstr;
 }

html代码

<input type="checkbox" name="frm_tag[]" id="frm_tag" value="1">1
<input type="checkbox" name="frm_tag[]" id="frm_tag" value="2">2

处理表单的PHP页面代码：

if(!empty($_POST['sport'])){
    echo('您的选择结果是：');
    for($i=0; $i<count($_POST['form1']);$i++){
          echo($_POST['sport'][$i].'    ');
    }
}

<input type="checkbox" name="weeks[]" id="weeks" value=1>
<input type="checkbox" name="weeks[]" id="weeks" value=2>
<input type="checkbox" name="weeks[]" id="weeks" value=3>

直接

$a = $_POST['weeks'] ;//这样得到的就是一个数组了，然后再把它转换成字符即可。

<input name="orderby[78]" type="text" id="ordery" size="5" value="9999" />
<input name="orderby[77]" type="text" id="ordery" size="5" value="999" />
<input name="orderby[76]" type="text" id="ordery" size="5" value="9999" />
<input name="orderby[75]" type="text" id="ordery" size="5" value="99" />
<input name="orderby[74]" type="text" id="ordery" size="5" value="9" />

php处理页面

$aid = $_POST['orderby'];  

foreach( $aid as $v=> $vv )
{
 if( is_numeric( $vv ) )
 {
  //更新排序即可了
 }
   
}

<?php
//密码验证
$password = "zongzi_Abc_oo13a2";
$n = preg_match_all("/^[a-zA-Zd_]{8,}$/",$password,$array);
//长度是8或更多
var_dump($array);
?>

<?php
$filename = "中文 文件名.txt";
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename=' . $filename);
print "Hello!";
?>

<?php
    $file = "/tmp/中文名.tar.gz";

    $filename = basename($file);

    header("Content-type: application/octet-stream");

    //处理中文文件名
    $ua = $_SERVER["HTTP_USER_AGENT"];
    $encoded_filename = urlencode($filename);
    $encoded_filename = str_replace("+", "%20", $encoded_filename);
    if (preg_match("/MSIE/", $ua)) {
     header('Content-Disposition: attachment; filename="' . $encoded_filename . '"');
    } else if (preg_match("/Firefox/", $ua)) {
     header("Content-Disposition: attachment; filename*="utf8''" . $filename . '"');
    } else {
     header('Content-Disposition: attachment; filename="' . $filename . '"');
    }

    header('Content-Disposition: attachment; filename="' . $filename . '"');
    header("Content-Length: ". filesize($file));
    readfile($file);
?>

<?php

trim 去除一个字符串两端空格，
rtrim 是去除一个字符串右部空格，
ltrim 是去除一个字符串左部空格。

echo trim(" 空格 ")."<br>";
echo rtrim(" 空格 ")."<br>";
echo ltrim(" 空格 ")."<br>";

?>

function trimall($str)//删除空格
{
 $qian=array(" ","　","t","n","r");
         $hou=array("","","","","");
 return str_replace($qian,$hou,$str); 
}

$str = " This line containstliberal rn use of whitespace.nn";

// First remove the leading/trailing whitespace
//去掉开始和结束的空白
$str = trim($str);

// Now remove any doubled-up whitespace
//去掉跟随别的挤在一块的空白
$str = preg_replace('/s(?=s)/', '', $str);

// Finally, replace any non-space whitespace, with a space
//最后，去掉非space 的空白，用一个空格代替
$str = preg_replace('/[nrt]/', ' ', $str);

// Echo out: 'This line contains liberal use of whitespace.'
echo "<pre>{$str}</pre>";