ADO.NET 3.5 Cookbook, 2nd Edition

2.1. Creating a DataColumn and Adding It to a DataTable

Problem

You need to create a column and add it to a DataTable.

Solution

Use the Add() or AddRange() method of the DataColumnCollection of the DataTable exposed through its Columns property.

The solution creates, configures, and adds a column to a DataTable using four different techniques:

• Adds a DataColumn to a DataTable and configures the column

• Creates and configures a DataColumn and adds it to a DataTable

• Adds a DataColumn to a DataTable and configures it using the Add() method of the ColumnCollection of the DataTable exposed through the Columns property

• Creates multiple DataColumn objects, configures them, and adds them to the DataTable using the AddRange() method of the ColumnCollection of the DataTable

The C# code in Program.cs in the project CreateDataColumnAddDataTable is shown in Example 2-1.

Example 2-1. File: Program.cs for CreateDataColumnAddDataTable solution

using System; using System.Data; namespace CreateDataColumnAddDataTable { class Program { static void Main(string[] args) { DataTable dt = new DataTable(); // Add the column to the DataTable to create DataColumn col1 = dt.Columns.Add(); // Configure the column -- integer with a default = 0 that // does not allow nulls col1.ColumnName= "Column-1"; col1.DataType = typeof(int); col1.DefaultValue = 0; col1.Unique = true; col1.AllowDBNull = false; // Create and configure the column DataColumn col2 = new DataColumn(); // Configure the column -- string with max length = 50 ...