asp.net SqlDataAdapter对象使用札记

2019-05-12 02:09:13王振洲

SqlCommand cmd;
SqlParameter parm;
// Create the SelectCommand.
cmd = new SqlCommand("SELECT * FROM Customers " +
"WHERE Country = @Country AND City = @City", conn);
cmd.Parameters.Add("@Country", SqlDbType.NVarChar, 15);
cmd.Parameters.Add("@City", SqlDbType.NVarChar, 15);
da.SelectCommand = cmd;
// Create the DeleteCommand.
cmd = new SqlCommand("DELETE FROM Customers WHERE CustomerID = @CustomerID", conn);
parm = cmd.Parameters.Add("@CustomerID", SqlDbType.NChar, 5, "CustomerID");
parm.SourceVersion = DataRowVersion.Original;
da.DeleteCommand = cmd;
return da;
}
下面的实例将创建一个 SqlDataAdapter 并设置 SelectCommand 和 UpdateCommand 属性。假定已经创建一个 SqlConnection 对象。
public static SqlDataAdapter CreateCustomerAdapter(SqlConnection conn)
{
SqlDataAdapter da = new SqlDataAdapter();
SqlCommand cmd;
SqlParameter parm;
// Create the SelectCommand.
cmd = new SqlCommand("SELECT * FROM Customers " +
"WHERE Country = @Country AND City = @City", conn);
cmd.Parameters.Add("@Country", SqlDbType.NVarChar, 15);
cmd.Parameters.Add("@City", SqlDbType.NVarChar, 15);
da.SelectCommand = cmd;
// Create the UpdateCommand.
cmd = new SqlCommand("UPDATE Customers SET CustomerID = @CustomerID, CompanyName = @CompanyName " +
"WHERE CustomerID = @oldCustomerID", conn);
cmd.Parameters.Add("@CustomerID", SqlDbType.NChar, 5, "CustomerID");
cmd.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40, "CompanyName");
parm = cmd.Parameters.Add("@oldCustomerID", SqlDbType.NChar, 5, "CustomerID");
parm.SourceVersion = DataRowVersion.Original;
da.UpdateCommand = cmd;
return da;
}