title: Type casting problem in code behind file
body: <p>I have the below error message in my asp.net website when i replaced the textbox and put dropdown and named the dropdown id same as textbox id.</p>
  
  <p>The value from the drop down should be taken and put in a email body and will be received as mail when i click on the submit button.</p>
  
  <p>Below is the error i am getting when i click on the submit button.</p>
  
  <blockquote>
    <p>System.InvalidCastException: Unable to cast object of type 'System.Web.UI.WebControls.DropDownList' to type 'System.Web.UI.WebControls.TextBox'. at WebApplication1._Default.collectEmailBodyText() in C:\v1.5_production_05June09\Default.aspx.vb:line 213 </p>
  </blockquote>
  
  <p>My code behind file is as follows :</p>
  
  <pre><code>''//------------------------------------------------------------------------------
  ''// &lt;auto-generated&gt;
  ''//     This code was generated by a tool.
  ''//     Runtime Version:2.0.50727.3053
  ''//
  ''//     Changes to this file may cause incorrect behavior and will be lost if
  ''//     the code is regenerated.
  ''// &lt;/auto-generated&gt;
  ''//------------------------------------------------------------------------------
  
  Option Strict On
  Option Explicit On
  
  Partial Public Class _Default
  
      Protected WithEvents form1 As Global.System.Web.UI.HtmlControls.HtmlForm
  
      Protected WithEvents MultiView1 As Global.System.Web.UI.WebControls.MultiView
  
      Protected WithEvents View0 As Global.System.Web.UI.WebControls.View
  
      Protected WithEvents lbl_viewTitle0 As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents lbl_view0_firstName As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_firstName As Global.System.Web.UI.WebControls.TextBox
  
      Protected WithEvents Validator_FirstName As Global.System.Web.UI.WebControls.RequiredFieldValidator
  
      Protected WithEvents lbl_view0_surname As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txtSurName As Global.System.Web.UI.WebControls.TextBox    
  
      Protected WithEvents Validator_Surname As Global.System.Web.UI.WebControls.RequiredFieldValidator
  
      Protected WithEvents lbl_view0_ContactNum As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_contactNum As Global.System.Web.UI.WebControls.TextBox
  
      Protected WithEvents Validator_ContactNumber As Global.System.Web.UI.WebControls.RequiredFieldValidator
  
      Protected WithEvents lbl_view0_typeOfRequest As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents ddl_view0_typeOfRequest As Global.System.Web.UI.WebControls.DropDownList
  
      Protected WithEvents lbl_view0_workUnitLevel As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents ddl_view0_workUnitLevel As Global.System.Web.UI.WebControls.DropDownList
  
      Protected WithEvents btn_view0_forward As Global.System.Web.UI.WebControls.Button
  
      Protected WithEvents View1 As Global.System.Web.UI.WebControls.View
  
      Protected WithEvents lbl_viewTitle1 As Global.System.Web.UI.WebControls.Label  
  
      Protected WithEvents lbl_view1_firstName As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_view1_firstname As Global.System.Web.UI.WebControls.TextBox
  
      Protected WithEvents lbl_view1_surname As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_view1_surname As Global.System.Web.UI.WebControls.TextBox
  
      Protected WithEvents lbl_view1_userID As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_view1_userID As Global.System.Web.UI.WebControls.TextBox
  
      Protected WithEvents lbl_view1_workUnit As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents ddl_view1_workunit As Global.System.Web.UI.WebControls.DropDownList
  
      Protected WithEvents panview0 As Global.System.Web.UI.WebControls.Panel
  
      Protected WithEvents lbl_panView0_label1 As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_panview0_input1 As Global.System.Web.UI.WebControls.TextBox
  
      Protected WithEvents panview2 As Global.System.Web.UI.WebControls.Panel
  
      Protected WithEvents lbl_panview2_label1 As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_panview2_input1 As Global.System.Web.UI.WebControls.TextBox
  
      Protected WithEvents panview1 As Global.System.Web.UI.WebControls.Panel
  
      Protected WithEvents lbl_panview1_label1 As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_panview1_input1 As Global.System.Web.UI.WebControls.TextBox   
  
      Protected WithEvents panview3 As Global.System.Web.UI.WebControls.Panel
  
      Protected WithEvents lbl_panview3_label1 As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_panview3_input1 As Global.System.Web.UI.WebControls.DropDownList
  
      Protected WithEvents lbl_panview3_label2 As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_panview3_input2 As Global.System.Web.UI.WebControls.TextBox
  
      Protected WithEvents btn_view1_back As Global.System.Web.UI.WebControls.Button
  
      Protected WithEvents btn_view1_forward As Global.System.Web.UI.WebControls.Button
  
      Protected WithEvents View2 As Global.System.Web.UI.WebControls.View
  
      Protected WithEvents lbl_viewTitle2 As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents lbl_view2_ManagersEmailAddress As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents txt_view2_ManagersEmailAddress As Global.System.Web.UI.WebControls.TextBox
  
      Protected WithEvents rfv_view2_managersEmail As Global.System.Web.UI.WebControls.RequiredFieldValidator
  
      Protected WithEvents rev_view2_managersEmail As Global.System.Web.UI.WebControls.RegularExpressionValidator
  
      Protected WithEvents btn_view2_back As Global.System.Web.UI.WebControls.Button  
  
      Protected WithEvents btn_view02_forward As Global.System.Web.UI.WebControls.Button
  
      Protected WithEvents View3 As Global.System.Web.UI.WebControls.View
  
      Protected WithEvents lbl_viewTitle3 As Global.System.Web.UI.WebControls.Label
  
      Protected WithEvents lit_preview As Global.System.Web.UI.WebControls.Literal
  
      Protected WithEvents btn_view3_submit As Global.System.Web.UI.WebControls.Button
  
      Protected WithEvents btn_view3_back As Global.System.Web.UI.WebControls.Button
  End Class
  </code></pre>
  
  <p>Please help me !</p>