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Tài liệu Finding Rows in a DataTable ppt
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[ Team LiB ]
Recipe 3.8 Finding Rows in a DataTable
Problem
You need to find a row or group of rows in a DataTable meeting certain criteria.
Solution
Choose from the three techniques shown in the sample code to locate data in the table
meeting user-specified criteria.
The sample code contains two event handlers:
Form.Load
Sets up the sample by creating a DataTable containing the Orders table from the
Northwind sample database. The default view of the table is bound to the data grid
on the form.
Find Button.Click
Uses three different techniques—the DataTable.Select( ) method, the
DataTable.Rows.Find( ) method, and the DataView.RowFilter property—to find
rows in the Orders table matching the user-specified Country.
The C# code is shown in Example 3-8.
Example 3-8. File: FindDataTableRowsForm.cs
// Namespaces, variables, and constants
using System;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
// Table name constants
private const String ORDERS_TABLE = "Orders";
// Field name constants
private const String ORDERID_FIELD = "OrderID";
private const String SHIPCOUNTRY_FIELD = "ShipCountry";