php 如何检查用户名是否已存在于codeigniter中
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/18498986/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
how to check if username already exists in codeigniter
提问by user2702406
I am working on a site in codeigniter.I am not so expert using framework.Here I have to check if email already exists in database.I have coded the required functionality but I am getting an error when submit the form. In controller i have made the following rule.
我正在使用 codeigniter 在一个网站上工作。我在使用框架方面不是很专业。在这里我必须检查电子邮件是否已经存在于数据库中。我已经对所需的功能进行了编码，但是在提交表单时出现错误。在控制器中，我制定了以下规则。
My code is:
我的代码是：
$this->form_validation->set_rules(
'email', 'Email', 'trim|required|valid_email|is_unique|callback_isEmailExist'
);
public function isEmailExist($email) {
$this->load->library('form_validation');
$this->load->model('user');
$is_exist = $this->user->isEmailExist($email);
if ($is_exist) {
$this->form_validation->set_message(
'isEmailExist', 'Email address is already exist.'
);
return false;
} else {
return true;
}
}
in model user the function is :
在模型用户中，函数是：
function isEmailExist($email) {
$this->db->select('id');
$this->db->where('email', $email);
$query = $this->db->get('users');
if ($query->num_rows() > 0) {
return true;
} else {
return false;
}
}
When I submit the form, I am getting the following errors.
当我提交表单时，我收到以下错误。
A PHP Error was encountered
遇到 PHP 错误
Severity: Notice
严重性：注意
Message: Undefined offset: 1
消息：未定义偏移量：1
Filename: libraries/Form_validation.php
文件名：库/Form_validation.php
Line Number: 953
行号：953
A Database Error Occurred
发生数据库错误
Error Number: 1064
错误编号：1064
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'WHERE ` = '[email protected]' LIMIT 1' at line 2
您的 SQL 语法有错误；检查与您的 MySQL 服务器版本相对应的手册，了解在第 2 行的“WHERE ` = '[email protected]' LIMIT 1' 附近使用的正确语法
SELECT * WHERE ` = '[email protected]' LIMIT 1
SELECT * WHERE ` = '[email protected]' 限制 1
Filename: C:\xampp\htdocs\aunction\system\database\DB_driver.php
文件名：C:\xampp\htdocs\aunction\system\database\DB_driver.php
Line Number: 330 Anyone help me please. Thanks in advance.
行号：330 请任何人帮助我。提前致谢。
采纳答案by Sharif
Your problem is in the set_rules line. Here you use both is_uniqueand a callbackfunction. You have to use anyone of that. If you use a call_back function to check duplicate data; doesn't need to use is_unique. For this wrong you get that errorJust remove the is_uniquefrom there.
您的问题出在 set_rules 行中。在这里您可以同时使用is_unique和 一个callback函数。你必须使用任何一个。如果使用 call_back 函数检查重复数据；不需要使用 is_unique。For this wrong you get that error只需is_unique从那里删除。
$this->form_validation->set_rules('email','Email','trim|required|valid_email|callback_isEmailExist'); // removed is_unique
Try this out and let me know.
试试这个，让我知道。
回答by Nikunj Dhimar
$this->form_validation->set_rules('username', 'userName', 'required|callback_exists_username');
#uniqueness of username
function exists_username($str)
{
$record_id = $this->input->post('record_id');
$condition = array('user_id !='=>$record_id,'username'=>$str);
$value =GetAllRecord('user_master',$condition,$is_single=true);
if (count($value) == 0)
{
return TRUE;
}
else
{
$this->form_validation->set_message('exists_username', 'username already exists!');
return FALSE;
}
}
回答by bikram kc
Just add is_unique[tablename.fieldname]rules to the form validation. for Example:
只需is_unique[tablename.fieldname]向表单验证添加规则即可。例如：
array('field' => 'email', 'label' => 'Email', 'rules' => 'trim|required|valid_email|is_unique[users.email]'));
回答by Kiran Shrestha
you can check if a field is unique or not by using form_validator function is_unique[table_name.field_name]
您可以使用 form_validator 函数检查字段是否唯一 is_unique[table_name.field_name]
回答by Sizzling Code
Your Model is like
你的模型就像
$this->db->select('id');
$this->db->where('email', $email);
please tell the mysql from which table you want to get the record.
请告诉mysql你想从哪个表中获取记录。
$this->db->from('tablename');
$this->db->from('tablename');
it would be like
它会像
$this->db->select('id');
$this->db->from('tablename');
$this->db->where('email', $email);
回答by abhinsit
You have an error in the mysql query:-
您在 mysql 查询中有错误：-
SELECT * WHERE ` = '[email protected]' LIMIT 1
Your code has not specified which table to query from. So use following:-
您的代码未指定要查询的表。所以使用以下： -
$this->db->select('id');
$this->db->from('tablename');
$this->db->where('email', $email);
Hope this helps.
希望这可以帮助。
回答by Dave Driesmans
no need to a make a special function, this is enough
不需要做一个特殊的功能，这就够了
$this->form_validation->set_rules(
'email', 'Email', 'trim|required|valid_email|is_unique'
);
回答by Avin Varghese
Use is_unique[table.field]add table name and field.
使用is_unique[table.field]添加表名和字段。
$this->form_validation->set_rules(
'email', 'Email', 'trim|required|valid_email|is_unique[table.field]|callback_isEmailExist'
);
