title: implode explode data in codeigniter
body: <p>I am using multiple select from a select drop down and I want to store it in database.</p>
  
  <p>I have heard about implode explode, but I have no idea how to use them. Please give me an idea how to implode and explode in codeigniter.</p>
  
  <p>My HTML form:</p>
  
  <pre><code>&lt;div class="form-group"&gt;
      &lt;label&gt;
          Please Select Proof Of ID Deposit
      &lt;/label&gt;
      &lt;select multiple="" name="oids" class="js-example-basic-multiple js-states form-control"&gt;
          &lt;optgroup&gt;
              &lt;option value="Passport"&gt;Passport&lt;/option&gt;
              &lt;option value="National ID Card"&gt;National ID Card&lt;/option&gt;
              &lt;option value="Driving Licence"&gt;Driving Licence&lt;/option&gt;
              &lt;option value="Univesity ID"&gt;Univesity ID&lt;/option&gt;
          &lt;/optgroup&gt;
      &lt;/select&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>My controller:</p>
  
  <pre><code>public function customer_insert(){
      $data = array(
          'id'=&gt;$this-&gt;input-&gt;post('up_id'),
          'Other_id'=&gt;$this-&gt;input-&gt;post('oids') //here I want to implode my values
      )
      $this-&gt;db-&gt;insert('customer', $data);
  }
  </code></pre>
  
  <p>View file:</p>
  
  <pre><code>&lt;table&gt;
      &lt;thead&gt;
          &lt;tr&gt;&lt;td&gt;ID&lt;/td&gt;&lt;/tr&gt;
          &lt;tr&gt;&lt;td&gt;Other ID&lt;/td&gt;&lt;/tr&gt;
      &lt;/thead&gt;
  &lt;?php foreach ($query as $customer){?&gt;
      &lt;tr&gt;&lt;td&gt;&lt;?php echo $customer-&gt;id?&gt;&lt;/td&gt;&lt;/tr&gt;
      &lt;tr&gt;&lt;td&gt;&lt;?php echo $customer-&gt;Other_id?&gt;&lt;/td&gt;&lt;/tr&gt; // I want to show my imploded value here. 
  &lt;?php}?&gt;
  &lt;/table&gt;
  </code></pre>