title: Binding one ListItem to multiple dropdown in .NET Form
body: <p>Maybe this is a very simple question for you .NET guys but since I come from a MFC C++ dev teams, this behavior all got our dev team wondering what was going on. (In MFC, when we create a dropdown datasource, the source is shared but the value of each dropdown is not affected)</p>
  
  <p>It's a very simple situation. I have 3 dropdownlist in my form that ask for streets. The street you are on and the others 2 closest streets. Each of these dropdownlist have the same datasource. So what we did is that (by the way ComboList is just a class that inherit ListItem with some more functions)</p>
  
  <pre><code>//Combo Street
  ComboList cboNomRue = new ComboList();
  Tools.GetCombo(cboNomRue, Tools.ComboTypeRt.RT_NOM_RUE, true, true);
  ddlNomRue.DisplayMember = "Numero";
  ddlNomRue.ValueMember = "ID";
  ddlNomRue.DataSource = cboNomRue;
  
  //Combo Street From
  ddlDe.DisplayMember = "Numero";
  ddlDe.ValueMember = "ID";
  ddlDe.DataSource = cboNomRue;
  
  //Combo Street To
  ddlA.DisplayMember = "Numero";
  ddlA.ValueMember = "ID";
  ddlA.DataSource = cboNomRue;
  </code></pre>
  
  <p>Using this code, when the user change the value in ddlNomRue, the 3 dropdownlist change to that value! So to fix that, I did that.</p>
  
  <pre><code>//Combo Street
  ComboList cboNomRue = new ComboList();
  Tools.GetCombo(cboNomRue, Tools.ComboTypeRt.RT_NOM_RUE, true, true);
  ddlNomRue.DisplayMember = "Numero";
  ddlNomRue.ValueMember = "ID";
  ddlNomRue.DataSource = cboNomRue;
  
  ComboList cboNomRue2 = new ComboList(cboNomRue);
  ComboList cboNomRue3 = new ComboList(cboNomRue);
  
  //Combo Street From
  ddlDe.DisplayMember = "Numero";
  ddlDe.ValueMember = "ID";
  ddlDe.DataSource = cboNomRue2;
  
  //Combo Street To
  ddlA.DisplayMember = "Numero";
  ddlA.ValueMember = "ID";
  ddlA.DataSource = cboNomRue3;
  </code></pre>
  
  <p>I don't like this since it's duplicating variables when only one is really needed. Is this the good way of dealing with this situation or is there anything else I could do?</p>
  
  <p>Thanks</p>