image not uploaded to specified folder in codeigniter - codeigniter

Question

I am trying to simply upload a image to a specified folder but cant figure out why is the controller function not working.Here is the controller code
public function do_upload()
{
$config['upload_path'] = './uploads/';
$config['allowed_types'] = 'gif|jpg|png';
$config['max_size'] = '400';
$config['max_width'] = '1024';
$config['max_height'] = '768';
$this->load->library('upload',$config);
if($this->upload->do_upload()){
echo "image uploaded";
}
echo $this->input->post('username');
}
And this is the form to input image file in view folder
<form enctype="multipart/form-data" method="post" action="<?php echo site_url('welcome/do_upload');?>">
username:<input type="text" name="username">
<p>upload file</p>
<input type="file" name="image">
<input type="submit" name="submit" value="submit">
</form>

Answer 1

You just need to pass file input name 'image' in do_upload function, by default its 'userfile'
public function do_upload()
{
$config['upload_path'] = './uploads/';
$config['allowed_types'] = 'gif|jpg|png';
$config['max_size'] = '400';
$config['max_width'] = '1024';
$config['max_height'] = '768';
$this->load->library('upload',$config);
if($this->upload->do_upload('image')){ //passed 'image' file control input name in form
echo "image uploaded";
}
echo $this->input->post('username');
}