无法访问与您的字段名称相对应的错误消息"

我猜想当一个字段没有值且没有必需的规则时会显示上述错误:

I guess Above error is shown when a field has no value and no required rule:

尝试如下设置规则

$this->form_validation->set_rules('g-recaptcha-response', 'Captcha', 'required|callback_recaptcha');

或(对于CI的最新版本)

$this->form_validation->set_rules(
        'g-recaptcha-response', /* Field */
        'Captcha',              /* Label */
         array(                 /* Rules */
                'required',
                array($this->your_model, 'recaptcha')
              )
);

OR

$this->form_validation->set_rules(
        'g-recaptcha-response', /* Field */
        'Captcha',              /* Label */
         array(                 /* Rules */
                'required',
                array('my_recaptcha', array($this->your_model, 'recaptcha'))
              ),
        array(                 /* Error lists */
              'my_recaptcha' => 'Invalid Recaptcha'
             )
);

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