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Creating AutoIncrement Columns

To ensure that the values in a column are unique, you can set the column values to increment automatically when new rows are added to the table. To create an auto-incrementing DataColumn, set the AutoIncrement property of the column to true. The DataColumn will then start with the value defined in the AutoIncrementSeed property, and with each row added the value of the AutoIncrement column will increase by the value held in the AutoIncrementStep property of the column.

For AutoIncrement columns, it is recommended that the ReadOnly property of the DataColumn be set to true.

The following example demonstrates how to create a column that starts with a value of 200 and adds incrementally in steps of three.

Dim workColumn As DataColumn = workTable.Columns.Add("CustomerID", typeof(Int32))
workColumn.AutoIncrement = true
workColumn.AutoIncrementSeed = 200
workColumn.AutoIncrementStep = 3
DataColumn workColumn = workTable.Columns.Add("CustomerID", typeof(Int32));
workColumn.AutoIncrement = true;
workColumn.AutoIncrementSeed = 200;
workColumn.AutoIncrementStep = 3;

See Also

Creating and Using DataTables | DataColumn Class