Cannot populate field when using form_helper in Codeigniter - php

Question

form were populating working in my previous project but now it isn't. I checked the code on my previous project and copy pasted it but still it doesn't populate it. When I type in it and submit it, it shows blank but when i inspected it in the browser it showed something like this:
check this image
Below is the my view:
<div class="form-group">
<?php echo form_hidden('STUD_ID', #$upd->STUD_ID); ?>
<?php echo form_label('Student name','name'); ?>
<?php echo form_input("STUD_NAME",#$upd->STUD_NAME,set_value('STUD_NAME'),["class"=>"form-control","placeholder"=>"John
Doe"]);?>
<?php echo form_error('STUD_NAME'); ?> </div> <div class="form-group">
<?php echo form_label('Password','password'); ?>
<?php echo form_input('STUD_PASS',#$upd->STUD_PASS,['class'=>'form-control','placeholder'=>'******']),set_value('STUD_PASS')
?>
<?php echo form_error('STUD_PASS'); ?> </div>
Controller
$this->form_validation->set_rules('STUD_NAME','Username','trim|required|is_unique[student.STUD_NAME]');
$this->form_validation->set_rules('STUD_PASS', 'Password', 'trim|required|min_length[5]');
$this->form_validation->set_rules('STUD_EMAIL', 'Email', 'trim|required|valid_email');
$this->form_validation->set_rules('STUD_ADD', 'Address', 'trim|required');
$this->form_validation->set_rules('STUD_PHONE', 'Phone', 'trim|required|min_length[10]');
$this->form_validation->set_rules('STUD_GENDER', 'Gender', 'trim|required');
$this->form_validation->set_rules('HOBBY[]', 'Hobby', 'trim|required');
$this->form_validation->set_error_delimiters('<small style="color:red">','</small>');
if ($this->form_validation->run() == TRUE) {
.......
}

Answer 1

Try with this code : initialise form_input with an array like this
Form should be like this :
<div class="form-group">
<?php echo form_hidden('STUD_ID', #$upd->STUD_ID); ?>
<?php echo form_label('Student name','name'); ?>
<?php echo form_input(["name" => "STUD_NAME","value" => set_value('STUD_NAME',#$upd->STUD_NAME),"class"=>"form-control","placeholder"=>"JohnDoe"]);?>
<?php echo form_error('STUD_NAME'); ?>
</div>
<div class="form-group">
<?php echo form_label('Password','password'); ?>
<?php echo form_input(["name" => "STUD_PASS","value" => set_value('STUD_PASS',#$upd->STUD_PASS),"class"=>"form-control","placeholder" => "******"]);?>
<?php echo form_error('STUD_PASS'); ?>
</div>
See more : https://www.codeigniter.com/user_guide/helpers/form_helper.html#form_input