ADO.NET in a Nutshell

Name

CommandText

Synopsis

String commandText = Command.CommandText;

Command.CommandText = commandText;

Defines the action that’s taken when this command executes. The meaning of the CommandText property depends on the value of the CommandType property. If CommandType is Text (the default), it’s the text of a SQL statement (such as SELECT * FROM Customers). If CommandType is StoredProcedure, it’s the name of the stored procedure that’s executed. If CommandType is TableDirect, it’s the name of a table that’s returned or a comma-delimited list of tables that’s joined and returned.

Example

The following example defines a Command and sets the CommandText with a SQL INSERT statement. When executed, this Command creates a new row.

string connectionString = "Data Source=localhost;" +

  "Initial Catalog=Northwind;Integrated Security=SSPI";



string sQL = "INSERT INTO Categories (CategoryName, Description) " +

              "VALUES ('Beverages', 'Soft drinks')";



SqlConnection con = new SqlConnection(connectionString);

SqlCommand cmd = new SqlCommand();



cmd.Connection = con;

cmd.CommandText = sQL;



int rowsAffected;

try

{

    con.Open();



    // Execute the command.

    rowsAffected = cmd.ExecuteNonQuery();

}

finally

{

    con.Close();

}

Notes

You can set two properties of the Command object—the linked Connection and the CommandText—using an overloaded constructor when you create the Command:

SqlCommand cmd = new SqlCommand(commandText, con);

This is usually the easiest approach to setting these properties. You can then reuse the