C# Coding issue with Drop Down List

Question

First, let me tell you what error I am getting.

'DDLTesttoAppear' has a SelectedIndex which is invalid because it does not exist in the list of items. Parameter name: value

I have many enums in my project, Here two enums are related two this question. This Two enums are

public enum Gender
{
    NA = 0, Male = 1, Female = 2
}

and

public enum NumberOfAdmissionTest
{
    NA = 0, First = 1, Second = 2, Third = 3, Fourth =4
}

In UI page I have two DDls they are like

DDLGender.DataSource = Enum.GetNames(typeof(Gender));
DDLGender.DataBind();

DDLTestApearnce.DataSource = Enum.GetNames(typeof(NumberOfAdmissionTest));
DDLTestApearnce.DataBind();

This fields can be inserted as null into the database. Therefore, while returning the record I am using a null hander function where the line of code to execute is that

candidateEntity.CandidateGender = nullHandler.GetInt32(CANDIDATE_GENDER);
candidateEntity.TestToAppear = nullHandler.GetInt32(TEST_TO_APPEAR);

public int GetInt32(String sFieldName)
{
    return (_reader[sFieldName] == DBNull.Value) ? 0 : _reader.GetInt32(_reader.GetOrdinal(sFieldName));
}

After retrieving the record, I am binding this with two ddls like

DDLGender.SelectedIndex = candidateEntity.CandidateGender;
DDLTesttoAppear.SelectedIndex = candidateEntity.TestToAppear;

Now, the interesting or confusing, whatever you say, part of this problem is that for gender, it's not generating any error, but for test appearance it's generating the error.

Answer 1

You are binding DDLTestApearnce in your sample, but are getting the error (and setting the selected value) on DDLTesttoAppear.