Php 所需下拉菜单不在codeigniter中工作

我想让邮件是必填字段，但不知何故它不起作用，我是不是遗漏了什么

升级电子邮件ID
Codeigniter下拉验证示例

<?php  echo form_label("Country:
","country");
     $data = array(
          "selectcountry"  => "Select Country",               
          "CA" => "Canada",
          "US" => "United States",
          "ZW" => "Zimbabwe"
                  );
     echo form_dropdown('country', $data, 'selectcountry');?>

Codeigniter下拉验证示例

<?php  echo form_label("Country:
","country");
     $data = array(
          "selectcountry"  => "Select Country",               
          "CA" => "Canada",
          "US" => "United States",
          "ZW" => "Zimbabwe"
                  );
     echo form_dropdown('country', $data, 'selectcountry');?>

注意到代码中的几个问题。
必需
&
数组
拼写错误，而且
表单下拉（）函数中最后一个参数使用的语法错误

试试这个

<div class="col-md-5 ">
  <div class="control-group form-group">
    <label class="control-label">
      Escalation Email Ids
    </label>
    <div class="controls">
      <?php $options=array(); if(count($useridsoptions)){ foreach($useridsoptions as $key=>$val){ $options[$key]=$val; } } echo form_dropdown('esc_users[]', $options, explode(",",$row->esc_users),'id="esc_users" class="form-control function col-md-12 select2" required="required" multiple'); ?>
    </div>
  </div>
</div>


升级电子邮件ID
注意到代码中的几个问题。
必需
&
数组
拼写错误，而且
表单下拉（）函数中最后一个参数使用的语法错误

试试这个

<div class="col-md-5 ">
  <div class="control-group form-group">
    <label class="control-label">
      Escalation Email Ids
    </label>
    <div class="controls">
      <?php $options=array(); if(count($useridsoptions)){ foreach($useridsoptions as $key=>$val){ $options[$key]=$val; } } echo form_dropdown('esc_users[]', $options, explode(",",$row->esc_users),'id="esc_users" class="form-control function col-md-12 select2" required="required" multiple'); ?>
    </div>
  </div>
</div>


升级电子邮件ID