//验证登陆表单
public function checkLogin(){
$username=I('name','');
$password=I('password','');
$verify_code = I('param.verifyid','');
if($username==''||$password==''||$verify_code==''||$verify_code==''){
$this->redirect(MODULE_NAME.".php/Login/index");
}

if(!$this->check_verify($verify_code)){
$this->error("验证码错误！！");
}

}

//验证码
public function verify(){
$Verify = new \Think\Verify();
$Verify->fontSize = 28;
$Verify->length = 4;
$Verify->useCurve = false;
$Verify->codeSet = '0123456789';
$Verify->imageH = 50;
$Verify->imageW = 270;
$Verify->entry(1);
}

/**
* 验证码检查
*/
function check_verify($code, $id = ""){
$verify = new \Think\Verify();
return $verify->check($code, $id);
}