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HomeBackend DevelopmentPHP Tutorial怎么隐藏下拉框的值

假设 php网站中



如果在数据库中 有1 服务类 的记录 

那么下次提交表单的时候  隐藏  这条  

怎么实现?


回复讨论(解决方案)

<?php$exists = array(1,2); // 这个表示从数据库中读取到已经有的记录。放到这个数组中,读数据库你自己写就可以了。?><select id="hangye" name="hangye"><option value="0">请选择</option><?if(!in_array(1, $exists)){?><option value="1">服务类</option><?}?><?if(!in_array(2, $exists)){?><option value="2">制造类</option><?}?><?if(!in_array(3, $exists)){?><option value="3">广告类</option><?}?></select>

<?php$exists = array(1,2); // 这个表示从数据库中读取到已经有的记录。放到这个数组中,读数据库你自己写就可以了。?><select id="hangye" name="hangye"><option value="0">请选择</option><?if(!in_array(1, $exists)){?><option value="1">服务类</option><?}?><?if(!in_array(2, $exists)){?><option value="2">制造类</option><?}?><?if(!in_array(3, $exists)){?><option value="3">广告类</option><?}?></select>



你好聪明啊  我怎么都没想到 in_array() 函数 

但是我怎么取值不出来?

假设我的数据表是  TABLE 其中有3条信息 
id  uid  name
1    2    张三
2    8    李四
3    9    王二

$result = mysql_query("SELECT * FROM uid",TABLE);
$row = mysql_num_rows($result);
输出$row不对

$result = mysql_query("SELECT * FROM uid",TABLE);
from uid明显有问题


改为
$uid=xxx; // 要查询的uid
$result = mysql_query("SELECT * FROM TABLE where uid='".$uid."'") or die(mysql_error());
试试

$result = mysql_query("SELECT * FROM uid",TABLE);
from uid明显有问题


改为
$uid=xxx; // 要查询的uid
$result = mysql_query("SELECT * FROM TABLE where uid='".$uid."'") or die(mysql_error());
试试




我不是要查询一条信息 不是你楼上2楼说了吗 我想用这个办法取得 所有uid的数据 输出的结果是 2,8,9 这种类型的数组
再用in_array() 判断下拉框啊 

那更简单

$query = mysql_query("select uid from TABLE") or die(mysql_error());$result = array();while($thread=mysql_fetch_assoc($query)){    $result[] = $thread['uid'];}

$result里面就是已经存在的uid了。

那更简单

$query = mysql_query("select uid from TABLE") or die(mysql_error());$result = array();while($thread=mysql_fetch_assoc($query)){    $result[] = $thread['uid'];}

$result里面就是已经存在的uid了。



输出为 Array 
怎么解决

那更简单

$query = mysql_query("select uid from TABLE") or die(mysql_error());$result = array();while($thread=mysql_fetch_assoc($query)){    $result[] = $thread['uid'];}

$result里面就是已经存在的uid了。



有不用 while循环 或者 while外部输出的办法吗

把$result带进$exists答案不就出来了?

把$result带进$exists答案不就出来了?



不行的


那更简单

$query = mysql_query("select uid from TABLE") or die(mysql_error());$result = array();while($thread=mysql_fetch_assoc($query)){    $result[] = $thread['uid'];}

$result里面就是已经存在的uid了。



输出为 Array 
怎么解决

数组输出当然是Array

这样你应该懂了吧。
$query = mysql_query("select uid from TABLE") or die(mysql_error());$result = array();while($thread=mysql_fetch_assoc($query)){    $result[] = $thread['uid'];} ?>



那更简单

$query = mysql_query("select uid from TABLE") or die(mysql_error());$result = array();while($thread=mysql_fetch_assoc($query)){    $result[] = $thread['uid'];}

$result里面就是已经存在的uid了。



输出为 Array 
怎么解决

数组输出当然是Array

这样你应该懂了吧。
$query = mysql_query("select uid from TABLE") or die(mysql_error());$result = array();while($thread=mysql_fetch_assoc($query)){    $result[] = $thread['uid'];} ?>



懂了 好了 谢谢了 
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