从下拉列表中选择值后,下次不会显示任何值


After selecting the value from dropdown list then it shows no any value next time

不工作:-从下拉列表中选择值后,提交后下一次显示没有任何值

Working:—但是最后选择的值保存在会话中。如果页面被刷新,会话值显示在下拉列表中选择。

Working:—任何关键字提交后,下拉框中的值必须显示。

请给我解决方案,使第一个工作。我已经使用POST

下面是我的代码:

<?php
session_start();
$selected='';
$offer_type_selected='';
function get_options($select)
{
    $incent_type=array('All'=>'none','Incent'=>'Incent','Non-Incent'=>'Non-Incent');
    $options='';
    while(list($k,$v)=each($incent_type))
    {
        if($select==$v)
        {
            $options.='<option value="'.$v.'" selected>'.$k.'</option>';   
        }
        else
        {
            $options.='<option value="'.$v.'">'.$k.'</option>';
        }        
    }
    return $options; 
}
if(isset($_POST['incent_type']))
    {
     $selected=$_POST['incent_type'];
     echo $selected;
      $_SESSION['incent_type']=$selected;
    }
?>
<body link="white">
<div class="container">
        <div class="content" >
           <form action="<?php echo $_SERVER['PHP_SELF'];?>" method="POST">
                <div class="label_div">Type a keyword :</div>
                <div class="input_container">
                    <input type="text" name="subquery" id="name_id" onkeyup="autocomplet()">
                    <ul id="name_list_id"></ul>                    
                </div>
                <div class="lable_div" >
                    <input type="submit" class="submit_query" name="submit_id" value="Submit Query" >
                    Select Incent Type :<select class="custom-dropdown" name="incent_type" onchange="this.form.submit();">
                        <?php 
                        $flag=0;
                        if(isset($_POST['subquery']))
                        {
                            if(strcmp("",$_POST['subquery'])!=0)
                            {
                                unset($_SESSION['incent_type']);
                                unset($_SESSION['offers_type']);
                                echo get_options('none');
                                $flag=1;
                            }                            
                        }
                        else if(isset($_SESSION['incent_type']) && $flag==0)
                             echo get_options($_SESSION['incent_type']);
                        else if($flag==0)
                            echo get_options('none');
                        ?>
                    </select>
                   </div>
            </form>
    </div>  
</div>

检查$_POST['subquery']有问题,你总是得到true - if(isset($_POST['subquery'])),尝试更改为if(!empty($_POST['subquery']))

也可以删除会话和一些if:

<?php
function get_options($select=null)
{
    $incent_type=array('All'=>'none','Incent'=>'Incent','Non-Incent'=>'Non-Incent');
    $options='';
    foreach($incent_type as $k=>$v){
        $options.='<option value="'.$v.'" '.(!empty($select) && $select==$v?"selected":"").'>'.$k.'</option>';  
    }
    return $options; 
}
?>
<body link="white">
<div class="container">
        <div class="content" >
           <form action="<?php echo $_SERVER['PHP_SELF'];?>" method="POST">
                <div class="label_div">Type a keyword :</div>
                <div class="input_container">
                    <input type="text" name="subquery" id="name_id" onkeyup="autocomplet()">
                    <ul id="name_list_id"></ul>                    
                </div>
                <div class="lable_div" >
                    <input type="submit" class="submit_query" name="submit_id" value="Submit Query" >
                    Select Incent Type :<select class="custom-dropdown" name="incent_type" onchange="this.form.submit();">
                        <?php 
                        echo get_options(empty($_POST['subquery'])?$_POST['incent_type']:null);
                        ?>
                    </select>
                   </div>
            </form>
    </div>  
</div>