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HomeBackend DevelopmentPHP Tutorial如何用php控制 select 中的选定值?

比如我有个select的表单

<select name="select_1"><option value=""></option><option value="value_1">option_1</option><option value="value_2">option_2</option>.....<option value="value_n">option_n</option></select></td>

最后的n也许会很大,我的设计是用户表单提交后,存入mysql,然后用户可以再编辑,那么在编辑页面,这个单选表单必须显示为mysql中的值为选中状态。我已经把mysql中的值读出来了是 $value_select_1,那怎么用php控制这个select_1表单将value为$value_select_1的值选中呢?

刚学php不久,希望不吝赐教。


回复讨论(解决方案)

数据库内的数据那就是已经保存的数据 输出的时候 取这个数值 1 然后 foreach 输出时判断这个数值是否相等,相等即是 selected.

数据库内的数据那就是已经保存的数据 输出的时候 取这个数值 1 然后 foreach 输出时判断这个数值是否相等,相等即是 selected.
版主 给我远程下巴
我那个环境还不行呢!!!!

数据库内的数据那就是已经保存的数据 输出的时候 取这个数值 1 然后 foreach 输出时判断这个数值是否相等,相等即是 selected.
妞妞  

$value_select_1=1;$select_arr=array('value_1','value_2','value_3','value_4');foreach ($select_arr as $value){    if(intval(substr($value,-1,1))==$value_select_1)        echo $value.' selected';}

$value_select_1=1;$select_arr=array('value_1','value_2','value_3','value_4');foreach ($select_arr as $value){    if(intval(substr($value,-1,1))==$value_select_1)        echo $value.' selected';}

谢谢版主,可是为什么是-1到1呢?


$value_select_1=1;$select_arr=array('value_1','value_2','value_3','value_4');foreach ($select_arr as $value){    if(intval(substr($value,-1,1))==$value_select_1)        echo $value.' selected';}

谢谢版主,可是为什么是-1到1呢?
明白了,就取最后一位,感谢!

<?phpecho '<select name="select_1" id="select_1">';echo '<option value=""></option>';for($i=1; $i<=10; $i++){    echo '<option value="value_'.$i.'">option_'.$i.'</option>';}echo '</select>';$cur = 10;echo '<script type="text/javascript">';echo 'document.getElementById("select_1").value = "value_'.$cur.'";';echo '</script>';?>

最好写成函数,提高代码的重复利用

<?phpecho '<select name="select_1" id="select_1">';echo '<option value=""></option>';for($i=1; $i<=10; $i++){    echo '<option value="value_'.$i.'">option_'.$i.'</option>';}echo '</select>';$cur = 10;echo '<script type="text/javascript">';echo 'document.getElementById("select_1").value = "value_'.$cur.'";';echo '</script>';?>

这个好,不过可惜我已经结帖了不能再给你分了,但还是表示非常感谢

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