thinkphp connection to MySQL database is always unsuccessful

When I use the thinkphp framework to connect to a database, it is always connected.
The code is as follows
config.php

return array(
     //'Configuration Item'=>'Configuration Value'
     //Static module access
     //'MODULE_DENY_LIST' => array('Common','Runtime','Admin'),
    
     //Allow access
     //'MODULE_ALLOW_LIST' => array('Home','Admin'),
     //Load module by default
 
         'DB_TYPE'=>'mysql',
         'DB_HOST'=>'localhost:8080',
         'DB_USER'=>'root',
         'DB_PWD'=>'123456789',
         'DB_PORT'=>'3306',
         'DB_NAME'=>'thinkphp',
         'DB_PREFIX'=>'think_',

);

And then in the class through method access, user is the name of the database
Public Function test () {

$user=new Model('User'); //Connect to the database
     var_dump($user->select());

  }
  He is always unsuccessful, what is the reason for this.

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When I use the thinkphp framework to connect to a database, it is always connected.
The code is as follows
config.php

return array(
     //'Configuration Item'=>'Configuration Value'
     //Static module access
     //'MODULE_DENY_LIST' => array('Common','Runtime','Admin'),
    
     //Allow access
     //'MODULE_ALLOW_LIST' => array('Home','Admin'),
     //Load module by default
 
         'DB_TYPE'=>'mysql',
         'DB_HOST'=>'localhost:8080',
         'DB_USER'=>'root',
         'DB_PWD'=>'123456789',
         'DB_PORT'=>'3306',
         'DB_NAME'=>'thinkphp',
         'DB_PREFIX'=>'think_',

);

And then in the class through method access, user is the name of the database
Public Function test () {

$user=new Model('User'); //Connect to the database
     var_dump($user->select());

  }
  He is always unsuccessful, what is the reason for this.

Configure 'DB_HOST'=>'localhost:8080'remove port '

Db_host inside just fill in the address, you should not understand the role of the configuration file, the rest of the port is the default or special by the Db_port to configure,
Even if something goes wrong, you can get the error message via M ()->geterror ().