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HomeBackend DevelopmentPHP Tutorial帮忙看看哪里错了,循环改数组中某值

dump($arr);

array(10) {
  [0] => array(21) {
    ["id"] => string(2) "88"       
    ........省略.........
    ["pu_pic"] => string(74) "1507/p_5594a950e92577.jpg|1507/p_5594a957e23c6.jpg|1507/p_5594a9518888.jpg"
    ........省略.........
  }
  [1] => array(21) {
    [0] => array(21) {
    ["id"] => string(2) "88"
    ........省略.........
    ["pu_pic"] => string(74) "1507/p_5594a950e1789.jpg|1507/p_4444a951e23c6.jpg|1507/p_5594a9544fb44.jpg"
    ........省略.........
  }
  [2] => array(21) {
    [0] => array(21) {
    ["id"] => string(2) "88"
    ........省略.........
    ["pu_pic"] => string(74) "1507/p_5594a950e1789.jpg|1507/p_4444a951e23c6.jpg|1507/p_5594a9544fb44.jpg"
    ........省略.........
  }


  源码

   循环改变$arr["pu_pic"]中的值

         for($i=0;$i if(strlen($arr[i]['pu_pic'])>30) //统计$arr["pu_pic"]中字符串个数
                 { 
$thumb=explode('|',$arr[i]['pu_pic']);
                $arr[i]['pu_pic']=$thumb[0];
}
         dump($thumb);  
 }

     dump($thumb)为空值;
    dump($arr); 中的值也没有改变


回复讨论(解决方案)

认真检查一下你的 $arr 数组
在你贴出的片段中,除 $arr[0] 是一维数组外,其他的都是二维数组
你的代码是按 $arr[n] 是一维数组设计的,显然除了 $arr[0] 以外都不会进入修改代码的

认真检查一下你的 $arr 数组
在你贴出的片段中,除 $arr[0] 是一维数组外,其他的都是二维数组
你的代码是按 $arr[n] 是一维数组设计的,显然除了 $arr[0] 以外都不会进入修改代码的



我片段中的数组是贴错了。不好意思!

整个数组$arr是一个二维数组

array(10) {
  [0] => array(21) {
    ["id"] => string(2) "74"
    ["pu_bt"] => string(14) "ssssssssssssss"
    ["pu_sfzj"] => string(1) "1"
    ["pu_lx"] => string(1) "1"
    ["pu_xjy"] => string(1) "0"
    ["pu_xjyb"] => string(0) ""
    ["pu_mj"] => string(2) "12"
    ["pu_zj"] => string(4) "3000"
    ["pu_qu"] => string(6) "天河"
    ["pu_qub"] => string(6) "车陂"
    ["pu_dz"] => string(0) ""
    ["pu_dh"] => string(7) "5555555"
    ["pu_lxr"] => string(0) ""
    ["pu_sm"] => string(0) ""
    ["pu_gk"] => string(0) ""
    ["pu_pic"] => string(74) "1507/p_55963e0e9685b.jpg|1507/p_55963e0eb388d.jpg|1507/p_55963e0ece755.jpg"
    ["puphoto1"] => string(0) ""
    ["puphoto2"] => string(0) ""
    ["puphoto3"] => string(0) ""
    ["thumburl"] => string(0) ""
    ["pu_time"] => string(10) "1435909646"
  }
  [1] => array(21) {
    ["id"] => string(2) "60"
    ["pu_bt"] => string(69) "非中介真实可靠!白云区广花路大型KTV酒吧转让出售"
    ["pu_sfzj"] => string(1) "1"
    ["pu_lx"] => string(1) "3"
    ["pu_xjy"] => string(3) "127"
    ["pu_xjyb"] => string(0) ""
    ["pu_mj"] => string(1) "4"
    ["pu_zj"] => string(5) "78000"
    ["pu_qu"] => string(1) "5"
    ["pu_qub"] => string(6) "广花"
    ["pu_dz"] => string(15) "广花大马路"
    ["pu_dh"] => string(11) "13660073733"
    ["pu_lxr"] => string(6) "阿娇"
    ["pu_sm"] => string(0) ""
    ["pu_gk"] => string(267) "白云区广花路现在有一处2600平方米营利中酒吧,证照齐全,内有大型KTV包房45间,加酒吧大厅,客源稳定,含路边带租约商铺7间,还有10年租期,现因老板全家移民,如有意者请电话联系,可前来考察。"
     ["pu_pic"] => string(74) "1507/p_55963e0e9685b.jpg|1507/p_55963e0eb388d.jpg|1507/p_55963e0ece755.jpg"
    ["puphoto1"] => string(0) ""
    ["puphoto2"] => string(0) ""
    ["puphoto3"] => string(0) ""
    ["thumburl"] => string(0) ""
    ["pu_time"] => string(10) "1434629313"
  }

$arr = array(  array( "pu_pic" => "1507/p_55963e0e9685b.jpg|1507/p_55963e0eb388d.jpg|1507/p_55963e0ece755.jpg"),  array( "pu_pic" => "1507/p_55963e0e9685b.jpg|1507/p_55963e0eb388d.jpg|1507/p_55963e0ece755.jpg"),);for($i=0; $i<count($arr); $i++) {  if(strlen($arr[$i]['pu_pic']) > 30) {    $thumb = explode('|', $arr[$i]['pu_pic']);    $arr[$i]['pu_pic'] = $thumb[0];  }}print_r($arr);
Array(    [0] => Array        (            [pu_pic] => 1507/p_55963e0e9685b.jpg        )    [1] => Array        (            [pu_pic] => 1507/p_55963e0e9685b.jpg        ))

没有问题呀

$arr = array(  array( "pu_pic" => "1507/p_55963e0e9685b.jpg|1507/p_55963e0eb388d.jpg|1507/p_55963e0ece755.jpg"),  array( "pu_pic" => "1507/p_55963e0e9685b.jpg|1507/p_55963e0eb388d.jpg|1507/p_55963e0ece755.jpg"),);for($i=0; $i<count($arr); $i++) {  if(strlen($arr[$i]['pu_pic']) > 30) {    $thumb = explode('|', $arr[$i]['pu_pic']);    $arr[$i]['pu_pic'] = $thumb[0];  }}print_r($arr);
Array(    [0] => Array        (            [pu_pic] => 1507/p_55963e0e9685b.jpg        )    [1] => Array        (            [pu_pic] => 1507/p_55963e0e9685b.jpg        ))

没有问题呀




感谢!问题解决了。通过把您的代码和我写的代码,逐行对比,发现是我粗心大意造成的。把  【 $i 】写成了【 i 】
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