Windows Forms ComboBox DataBinding
<p>I'm working on a C# Windows Forms Application and my ComboBox DataBinding is not working correctly.</p>

<p>This is my Data Source<a href="https://i.stack.imgur.com/QpfVC.png" rel="nofollow"><img src="https://i.stack.imgur.com/QpfVC.png" alt="Form Data Source"></a></p>

<p>And this is how Data Source is filled.</p>

<pre><code>private void frmSODetails_Load(object sender, EventArgs e)
    {
        int soid = soSelected.soid;
        this.salesordersTableAdapter.Fill(this.dsSalesOrderDetails.salesorders, soid);
        this.solineitemsTableAdapter.Fill(this.dsSalesOrderDetails.solineitems, soid);
        this.companiesTableAdapter.Fill(this.dsSalesOrderDetails.companies);
        this.Cursor = Cursors.Default;
    }
</code></pre>

<p>This is my form
<a href="https://i.stack.imgur.com/5kzRU.png" rel="nofollow"><img src="https://i.stack.imgur.com/5kzRU.png" alt="Sales Order Details Form"></a></p>

<p>And this is how i do the DataBindings.
Select Data Source (companiesBindingSource)
<a href="https://i.stack.imgur.com/Kkiy7.png" rel="nofollow"><img src="https://i.stack.imgur.com/Kkiy7.png" alt="Selecting Data Source"></a>
Selecting Display Member (compname)
<a href="https://i.stack.imgur.com/Lm3ul.png" rel="nofollow"><img src="https://i.stack.imgur.com/Lm3ul.png" alt="Selecting Display Member"></a>
Selecting Value Member (seq)
<a href="https://i.stack.imgur.com/PxvLw.png" rel="nofollow"><img src="https://i.stack.imgur.com/PxvLw.png" alt="enter image description here"></a>
Selecting Selected Value (Column comp from salesordersBindingSource)
<a href="https://i.stack.imgur.com/oY3jm.png" rel="nofollow"><img src="https://i.stack.imgur.com/oY3jm.png" alt="enter image description here"></a>
To Make Sure (Selected Value: comp) and (Value Member: seq) matches i used Preview Data</p>

<p>Comp : 1
<a href="https://i.stack.imgur.com/QVQJ3.png" rel="nofollow"><img src="https://i.stack.imgur.com/QVQJ3.png" alt="enter image description here"></a>
Seq 1 should have a compname value of <strong>Ampleon</strong>
<a href="https://i.stack.imgur.com/gli7r.png" rel="nofollow"><img src="https://i.stack.imgur.com/gli7r.png" alt="enter image description here"></a></p>

<p>But the ComboBox does not show <strong>Ampleon</strong> it shows the first item on the list of Companies.
<a href="https://i.stack.imgur.com/igudy.png" rel="nofollow"><img src="https://i.stack.imgur.com/igudy.png" alt="enter image description here"></a></p>

<p>EDIT: I deleted the entire form and created a new one and it is working properly now. I am not sure what went wrong on the first form. I just followed the same steps.</p>