VB.NET數據庫實際范例解讀

作者：佚名 2010-01-08 10:37:50

開發后端

對于剛剛接觸VB.NET編程語言不久的朋友來說，可能對于如何操作數據庫產生一定的疑問。我們就一起通過這篇文章來一起看看VB.NET數據庫的基本代碼實現。

如今的一個程序開發中基本上都需要對數據庫進行一定的操作，才能完成整個程序的完善性。在這里我們會了解到有關VB.NET數據庫的一些操作方面的代碼實現，方便大家對這一方面的解讀。#t#

VB.NET數據庫代碼示例：

Imports System
Imports System.Data
Imports System.Data.SqlClient
public Class MainClassclass MainClass
Shared Sub Main()Sub Main()
Dim thisConnection As New SqlConnection
("server=(local)\SQLEXPRESS;" & _
"integrated security=sspi;database=
MyDatabase")
' Sql Query
Dim sql As String = "SELECT *
FROM Employee "
Dim insertSql As String = "INSERT
INTO Employee " & _
"(ID, FirstName, LastName)VALUES" & _
"(@ID, @FirstName, @LastName)"
Try
' Create Data Adapter
Dim da As New SqlDataAdapter
da.SelectCommand = New SqlCommand
(sql, thisConnection)
' Create and fill Dataset
Dim ds As New DataSet
da.Fill(ds, "Employee")
' Get the Data Table
Dim dt As DataTable = ds.Tables
("Employee")
' Display Rows Before Changed
Console.WriteLine("Before altering
the dataset")
For Each row As DataRow In dt.Rows
Console.WriteLine("{0} | {1} | {2}", _
row("ID").ToString().PadRight(10), _
row("FirstName").ToString().PadRight(10), _
row("LastName"))
Next
' Add A Row
Dim newRow As DataRow = dt.NewRow()
newRow("FirstName") = "Edna"
newRow("LastName") = "Everage"
newRow("ID") = "2"
dt.Rows.Add(newRow)
' Display Rows After Alteration
Console.WriteLine("=========")
Console.WriteLine("After
altering the dataset")
For Each row As DataRow In dt.Rows
Console.WriteLine("{0} | {1} | {2}", _
row("ID").ToString().PadRight(10), _
row("FirstName").ToString().PadRight(10), _
row("LastName"))
Next
' Insert employees
' 1. Create command
Dim insertCmd As New SqlCommand
(insertSql, thisConnection)
' 2. Map parameters
insertCmd.Parameters.Add("@FirstName", _
SqlDbType.NVarChar, 10, "FirstName")
insertCmd.Parameters.Add("@LastName", _
SqlDbType.NVarChar, 20, "LastName")
insertCmd.Parameters.Add("@ID", _
SqlDbType.Int, 15, "ID")
' 3. Insert employees
da.InsertCommand = insertCmd
da.Update(ds, "Employee")
Catch ex As SqlException
' Display error
Console.WriteLine("Error: "
& ex.ToString())
Finally
' Close Connection
thisConnection.Close()
Console.WriteLine("Connection
Closed")
End Try
End Sub
End Class

以上就是對VB.NET數據庫的應用代碼示例進行的詳細解讀，希望對大家有所幫助。

責任編輯：曹凱來源：博客園

VB.NET數據庫