Question

I have an Excel file and the columns have names (data source is NOT controlled by me.. it’s given to me by a client). Although the columns change, the column headers never change.

In the file, it’s called “First Name”

How do I access the data in every cell within the same column?

Answer 1

Open your Excel file as a database. Then you will not have to bother about the position of the columns:

string connString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\\MyExcelFile.xls;Extended Properties=\"Excel 8.0;HDR=YES\"";
using (var conn = new System.Data.OleDb.OleDbConnection(connString)) {
    conn.Open();
    System.Data.OleDb.OleDbCommand cmd = new System.Data.OleDb.OleDbCommand("Select * From [SheetName$]", conn);
    OleDbDataReader reader = cmd.ExecuteReader();
    int firstNameOrdinal = reader.GetOrdinal("First Name");
    int lastNameOrdinal = reader.GetOrdinal("Last Name");
    while (reader.Read()) {
        Console.WriteLine("First Name: {0}, Last Name: {1}", 
            reader.GetString(firstNameOrdinal), 
            reader.GetString(lastNameOrdinal));
    }
}