C# Set combo item with selectedValue
- by Martijn
I am dynamically creating a combobox like this:
public Control GenerateList(Question question)
{
// Get a list with answer possibilities
List<QuestionAnswer> answers = question.GetAnswers();
// Get a collection of given answers
Collection<QuestionnaireAnswer> givenAnswers = question.GetFilledAnswers();
ComboBox cmb = new ComboBox();
cmb.Name = "cmb";
cmb.DataSource = answers;
cmb.DisplayMember = "Answer";
cmb.ValueMember = "Id";
// Check an answer is given to the question
if (givenAnswers != null && givenAnswers.Count > 0)
{
cmb.SelectedValue = givenAnswers[0].AnswerId;
}
cmb.DropDownStyle = ComboBoxStyle.DropDownList;
cmb.SelectedIndexChanged += new EventHandler(cmb_SelectedIndexChanged);
cmb.Leave += new EventHandler(cmb_Leave);
return cmb;
}
The problem is,when executing cmb.SelectedValue = givenAnswers[0].AnswerId; cmb.SelectedValue is always null.
When debugging and I explore answers (the datasource) I see that Id (ValueMember) is exactle the same as AnswerId (in the if statement). Both have the same type (long) and the same value, but SelectedValue stays null.
Is there something I don't see?
