Add string to DataSet

Question

Hello,

I want to add to the DataSet in the highlighted line a variable of type string

How to do this?

private void fillExamList()

{

string selectExamination = "SELECT ExamType.ExamTypeString, FullName, ExamDate, ExamCode FROM ExamType INNER JOIN Examination ON ExamType.ExamType = Examination.ExamType WHERE PatientID = " + txtSearchID.Text + "";

SqlDataAdapter da = new SqlDataAdapter(selectExamination, conn);

DataSet ds = new DataSet();

try

{

conn.Open();

da.Fill(ds);

ds.Tables[0].Columns.Add("ExamList", typeof(string), "FullName + ', ' + ExamTypeString");

ddlExamList.DataValueField = "ExamCode";

ddlExamList.DataTextField = "ExamList";

ddlExamList.DataSource = ds;

ddlExamList.DataBind();

ddlExamList.Items.Insert(0, new ListItem("Select...", "0"));

}

catch (Exception ex)

{

ErrorHandling(ex.ToString());

}

finally

{

conn.Close();

}

}