Programatically add SPFieldChoice (with Choices) to List

Question

I have a list that I want to add a choice field to programatically. I also want to specify the choices. Here is the code:

var fieldChoice = (SPFieldChoice)list.Fields.CreateNewField("Choice", "FieldName");
fieldChoice.Choices.Add("Choice 1");
fieldChoice.Choices.Add("Choice 2");
list.Update();
fieldChoice.Update();

I've been playing around with the placement of the list.Update() and fieldChoice.Update() lines, but nothing seems to work. If I leave out fieldChoice.Update(), the field does not have any choices. If I inlcude fieldChoice.Update(), I get this exception:

System.ArgumentException was unhandled by user code
  Message=<nativehr>0x80070057</nativehr><nativestack></nativestack>
  Source=""
  StackTrace:
       at Microsoft.SharePoint.Library.SPRequestInternalClass.UpdateField(String bstrUrl, String bstrListName, String bstrXML)
       at Microsoft.SharePoint.Library.SPRequest.UpdateField(String bstrUrl, String bstrListName, String bstrXML)
       at Microsoft.SharePoint.SPField.UpdateCore(Boolean bToggleSealed)
       at Operations.Layouts.Operations.Main.CreateList(SPWeb web, String listName)
       at Operations.Layouts.Operations.Main.Page_Load(Object sender, EventArgs e)
       at System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e)
       at System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e)
       at System.Web.UI.Control.OnLoad(EventArgs e)
       at Microsoft.SharePoint.WebControls.UnsecuredLayoutsPageBase.OnLoad(EventArgs e)
       at Microsoft.SharePoint.WebControls.LayoutsPageBase.OnLoad(EventArgs e)
       at System.Web.UI.Control.LoadRecursive()
       at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
  InnerException:

What am I doing wrong?

Answer 1

I believe with that technique you are creating a Field object for that list but it does not actually add a column, similar to adding columns to a Datatable().

For creating fields via code I typically go with

 //Add Column to list
 //GUID SPList.Fields.ADD(name,type,required);
 list.Fields.Add("Field Name", SPFieldType.Choice, false);

 //Get Field Reference
 SPFieldChoice col = (SPFieldChoice) list.Fields["Field Name"];

 col.Choices.Add("option 1");
 col.Choices.Add("option 2");
 col.DefaultValue = "option 1"; //otherwise blank row by default.

 col.update();  //Saves choices to column

 list.update();

Answer 2

One hint is to use AddRange() method to add array of strings as choices instead of adding choices with Add() one by one

string[] Choices = { "choice1", "choice2", "choice3", "choice4", "choice5" };
col.Choices.AddRange(Choices);