Asp. NET: Saving Data using a DataTable object

Source: Internet
Author: User
Tags object end net window visual studio
Asp.net| Object | A DataSet object is a collection of data tables (DataTables), where multiple DataTable can be stored in a dataset. As a data source, a dataset can provide multiple data tables, which can be associated with tables in a dataset, and each DataTable object can also be used as a data source. The following example demonstrates how a DataTable object is provided to a DropDownList control to provide a data source.

Create a new Web form, named Datatable_simple.aspx, and add two DropDownList controls, as shown in the design window as 8.9.


Figure 8.9 datatable_simple.aspx Design window

To toggle the Datatable_simple.aspx HTML Code window, the HTML code is as follows:
<%@ Page language= "vb" autoeventwireup= "false" codebehind= "DataTable_Simple.aspx.vb" inherits= " Adodotnet.datatable_simple "%>
<! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 transitional//en" >
<HTML>
<HEAD>
<title> save data using DataTable </title>
<meta content= "Microsoft Visual Studio. NET 7.1" name= "generator" >
<meta content= "Visual Basic. NET 7.1" name= "Code_language" >
<meta content= "JavaScript" name= "vs_defaultClientScript" >
<meta content= "http://schemas.microsoft.com/intellisense/ie5"Name=" Vs_targetschema ">
</HEAD>
<body ms_positioning= "GridLayout" >
<form id= "Form1" method= "POST" runat= "Server" >
<font face= "Song Body" >
<table id= "Table1" cellspacing= "1" cellpadding= "1" width= "360" "border=" 1 "style=" width:360px; height:75px ">
<TR>
&LT;TD align= "Center" ><STRONG> use DataTable to save data </STRONG></TD>
</TR>
<TR>
<TD> section
<asp:dropdownlist id= "DropDownList1" runat= "Server" width= "107px" autopostback= "True" ></asp:dropdownlist The item value of the > item is-->
<asp:dropdownlist id= "DropDownList2" runat= "Server" ></asp:DropDownList></TD>
</TR>
</TABLE>
</FONT>
</form>
</body>
</HTML>
View the datatable_simple.aspx logical code (that is, the DataTable_Simple.aspx.vb file), where the logical code is as follows:
'--------cdoe begin----------
Public Class Datatable_simple
Inherits System.Web.UI.Page

#Region the code generated by the Web Forms Designer

' This call is required by the Web Forms Designer.
<system.diagnostics.debuggerstepthrough () > Private Sub InitializeComponent ()

End Sub
Protected WithEvents DropDownList1 as System.Web.UI.WebControls.DropDownList
Protected WithEvents DropDownList2 as System.Web.UI.WebControls.DropDownList

' NOTE: The following placeholder declarations are required by the Web Forms Designer.
' Do not delete or move it.
Private Designerplaceholderdeclaration as System.Object

Private Sub Page_Init (ByVal sender as System.Object, ByVal e as System.EventArgs) Handles Mybase.init
' CodeGen: This method call is required by the Web Forms Designer
' Do not modify it using the Code Editor.
InitializeComponent ()
End Sub

#End Region

Private Sub Page_Load (ByVal sender as System.Object, ByVal e as System.EventArgs) Handles MyBase.Load
' The user code to place the initialization page here
If not Page.IsPostBack Then
Dim myDT as DataTable
Dropdownlist1.datasource = DT ()
Dropdownlist1.datatextfield = "id"
Dropdownlist1.databind ()
Dropdownlist2.datasource = DT ()
Dropdownlist2.datatextfield = "Item"
Dropdownlist2.databind ()
End If
End Sub
' Generate DataTable object functions and generate data to store data in a DataTable object
Function DT () as DataTable

' Defines a DataTable object ' mydatatable ', and instantiates
Dim mydatatable as DataTable = New DataTable ("Mydatatable")

' Declare DataColumn object ' Mydatacolumn ' and DataRow object ' MyDataRow '
Dim Mydatacolumn as DataColumn
Dim MyDataRow as DataRow

' Materialized Mydatacolumn
Mydatacolumn = New DataColumn
Mydatacolumn.datatype = System.Type.GetType ("System.Int32")
Mydatacolumn.columnname = "id"
MYDATATABLE.COLUMNS.ADD (Mydatacolumn)

        ' Instantiate mydatacolumn
        Mydatacolumn = New DataColumn
        mydatacolumn.datatype = Type.GetType (" System.String ")
        mydatacolumn.columnname =" Item "
         myDataTable.Columns.Add (mydatacolumn)

' Instantiate MyDataRow and add to Mydatatable
Dim I as Integer
For i = 0 to 10
MyDataRow = Mydatatable.newrow
MyDataRow ("id") = I
MyDataRow ("item") = "Item" & I
MYDATATABLE.ROWS.ADD (MyDataRow)
Next I

' Return to Mydatatable
Return mydatatable
End Function

Private Sub dropdownlist1_selectedindexchanged (ByVal sender as System.Object, ByVal e as System.EventArgs) Handles Dropdo Wnlist1.selectedindexchanged
Dropdownlist2.selectedindex = Dropdownlist1.selectedindex
End Sub
End Class
'---------code end-----------
After you save the compilation, the Datatable_simple.aspx run as shown in Figure 8.10.


Figure 8.10 Datatable_simple.aspx Running effect



Related Article

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.