... the DataAdapter object.
Adding a DataRow to aDataTable
In this section, you'll learn how to add a DataRow to a DataTable. Before you see this,
let's populate a DataSet with the rows ... DataAdapter to push the new row to the
database.
The following method, named AddDataRow(), uses these steps to add a new row to a
DataTable:
public static void AddDataRow(
DataTable myDataTable, ...
myInsertCommand:
mySqlDataAdapter.InsertCommand = myInsertCommand;
Setting the UpdateCommand Property of a DataAdapter
The following example creates a SqlCommand object named myUpdateCommand...
... overloaded as follows:
int Update(DataRow[] myDataRows)
int Update(DataSet myDataSet)
int Update (DataTable myDataTable)
int Update(DataRow[] myDataRows, DataTableMapping myDataTableMapping)
int ...
CompanyName and Address are changed, and then to Unchanged after
mySqlDataAdapter.Update() is called.
where dataTableName is a string containing the name of the DataTable to update. The int
returned ... static void DisplayDataRow(
DataRow myDataRow,
DataTable myDataTable)
{
Console.WriteLine("\nIn DisplayDataRow()");
foreach (DataColumn myDataColumn in myDataTable.Columns)
...
... sample code contains two event handlers:
Form.Load
Sets up the sample by creating aDataTable containing the Orders table from the
Northwind sample database. The default view of the table is bound ...
You want to create a grid that shows the t op five rowsina DataTable, based on the
values in one of the columns.
Solution
Use an appropriate sort order with a DataView filter.
The sample ... Freight value involves
several steps. First, sort the DataView on the Freight field in descending order; this places
[ Team LiB ]
Recipe 3 .10 Selecting the Top n RowsinaDataTable
Problem...
... orderDetailsDataTable .Rows. Find(orderDetails);
Filtering and Sorting DataRow Objects inaDataTable
To filter and sort the DataRow objects ina DataTable, you use the Select() method of
your DataTable. ... Order Details DataTable
// to the OrderID and ProductID columns
DataTable orderDetailsDataTable = myDataSet.Tables["Order Details"];
orderDetailsDataTable.Constraints.Add(
"Primary ... it was modified.
None Doesn't match any of the rowsin the DataTable.
OriginalRows The original rows, which include Unchanged and Deleted rows.
Unchanged A row that hasn't been changed....
... ProductID";
SqlDataAdapter mySqlDataAdapter = new SqlDataAdapter();
mySqlDataAdapter.SelectCommand = mySelectCommand;
The SELECT statement is then run when you call the mySqlDataAdapter object's ... set ina DataAdapter object's
InsertCommand, UpdateCommand, and DeleteCommand properties.
The ability to call stored procedures using a DataAdapter is a very powerful addition to
ADO.NET. ... DELETE statement before the main
SQL statement in your stored procedure.
Setting Up a DataAdapter to Call Stored Procedures
As mentioned in the earlier section " ;Modifying Rowsina DataTable
,"...
... the DataTable, use an overload of the Select( ) method of
the DataTable to return an array of deleted DataRow objects. The overload accepts an
argument having a DataViewRowState enumeration value. ... Deleted rows from the DataTable, use an overload of the Select( ) method of
the DataTable to return an array of deleted DataRow objects. The overload accepts an
argument having a DataViewRowState ...
called.
Unchanged
The data in the row has not been changed since it was loaded or since
AcceptChanges( ) was last called.
When AcceptChanges( ) is called on the DataSet, DataTable, or DataRow,...
... some of these categories:
•
Data The Data category contains classes that allow you to access and store
information from a database. The Data category includes the following classes:
SqlConnection, ... changing the text in the
Name field; go ahead and enter MyWindowsApplication in the Name field, as shown in
Figure 6 .1
.
Figure 6 .1: Creating a C# Windows application in Visual Studio .NET ... Windows Application
In this section, you'll see how to create a simple Windows application using VS .NET.
This application will consist of a single form that contains a label and a button....
... Remote Desktop for Administration in Windows Server
2003. As was already mentioned earlier in this chapter, this facility is automatically
installed on all servers running Windows Server 2003. ... However, in cases when you are under a DoS attack, such behavior is
undesirable, since all traffic can be redirected to a gateway that is not constantly
monitored. Because of this reason, set ... these parameters and their recommended values are provided below:
EnableDeadGWDetect (REG_DWORD data type). The default value (1) enables
TCP/IP to switch to a secondary gateway if many connections...
... ADO.NET automatically stores database connections ina pool. Connection
pooling offers a great performance improvement because you don't have to wait for a
brand new connection to the database ... to a SQL Server database
*/
using System;
using System.Data;
using System.Data.SqlClient;
class MySqlConnection
{
public static void Main()
{
// formulate a string containing ... established when there's a suitable connection
already available. When you close a connection, that connection isn't actually closed;
instead, your connection is marked as unused and...
... Products DataTable. First, the following
example creates aDataTable object named productsDataTable and sets it to the Products
DataTable retrieved from myDataSet:
DataTable productsDataTable ... sort DataRow
objects ina DataTable. You'll learn how to do that later in the section "Finding, Filtering,
and Sorting Rowsina DataTable. "
Tip Adding constraints causes a performance ... adding a primary key constraint to your DataTable because you
don't want duplicate rows.
Adding a Primary Key to the Products DataTable
Let's take a look at adding a primary key...
...
// Nhớ lưu một tham chiếu đến AppDomain mới vì nó
// không thể được thu lấy theo bất kỳ cách nào khác.
AppDomain newDomain = AppDomain.CreateDomain(
"My New AppDomain",
new System.Security.Policy.Evidence(), ... viên ở đây.
System.Data.DataSet data1 = new System.Data.DataSet();
// Cấu hình/thêm dữ liệu cho DataSet.
§
// Đóng gói DataSet.
System.Runtime.Remoting.ObjectHandle objHandle =
new System.Runtime.Remoting.ObjectHandle(data1); ... đầy đủ.
string name1 = "System.Data,Version =1. 0.5000.0," +
"Culture=neutral,PublicKeyToken=b7 7a5 c5 619 34e089";
Assembly a1 = Assembly.Load(name1);
// Nạp assembly System.Xml...
... c a STTD. Danh sách các nội dung s a đổi được lập
theo cấu trúc sau:
S a
đổi lần
thứ
Ngày
tháng s a
đổi
Tham
chiếu
Tên gọi
phần s
a
đổi
Chương /
phần có
liên quan
Đại diện Ban ... LỤC 1A.
DANH MỤC VĂN BẢN PHÁP LÝ
Tên văn bản Số tham chiếu Ngày ban
hành
1. VĂN BẢN PHÁP LÝ
Pháp lệnh hợp đồng kinh tế 25/09 /19 89
Luật Dân sự nước Cộng hoà Xã
hội Chủ ngh a Việt Nam
...
hội Chủ ngh a Việt Nam
28 /10 /19 95
Luật các tổ chức tín dụng 12 /12 /19 97
Nghị định về quy chế đấu thầu 88 /19 99/NĐ-CP 01/ 09 /19 99
Nghị định về quy chế đấu thầu 14 /2000/NĐ-CP 05/05/2000
Thông...
... void HashtableAddTest()
{
Hashtable ht = new Hashtable();
ht.Add("Key1", "Value1");
ht.Add("Key2", "Value2");
Assert.AreEqual("Value1", ... được viết bởi Kamal Patel và có thể được download
tại [
http://www.kamalpatel.net
].
7. A. 13 Xây dựng website quản trị cơ sở dữ liệu
với ASP.NET Maker 1.1
ASP.NET Maker là một bộ sinh mã rất ...
name="M:NUnitExample.HashtableTest.HashtableAddTest">
<summary>This test adds a number of values to the
Hashtable
collection and then retrieves those values and
checks if
they match.
...