VB.net的特殊语法（区别于C#.NET）
1:引入命名空间（Imports）
Imports System.Exception Imports System.Data.SqlClient Imports System.Security.Cryptography Imports System.Text.StringBuilder
2：实例化类
Dim myConn As SqlConnection myConn = New SqlConnection(ConnString)
3：IF THEN ELSE END块
If Not IsPostBack() Then txtEmployee.Text = "" txtPassWord.Text = "" else txtEmployee.Text = " txtPassWord.Text = "" End If
4:Try catch Fanally End Try块
Try myConn = New SqlConnection(ConnString) myConn.Open()Catch ex As Exception Throw New Exception(ex.Message & "clsDatabaseAccess.GetDataBase()") Finally myConn.Close() myConn = Nothing End Try
5：Sub块
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load Try If Not IsPostBack() Then txtEmployee.Text = "" txtPassWord.Text = "" End If Catch ex As Exception Response.Write(ex.Message) End Try End Sub
6：函数块（function）
Private Function ByteArrayToString(ByVal arrInput() As Byte) As String Dim i As Integer Dim sOutput As New System.Text.StringBuilder(arrInput.Length) For i = 0 To arrInput.Length - 1 sOutput.Append(arrInput(i).ToString("X2")) Next Return sOutput.ToString() End Function
7：变量定义
Dim bytMessage As Byte() Dim bytMD5 As Byte() Dim strMD5 As String Dim strPassword As String Dim Readlen As Integer
'数组定义
Dim tTfile() As String = Split(tfileN.Trim, "\")
Dim MD5 As New System.Security.Cryptography.MD5CryptoServiceProvider
8：数据库连接获取DS方法
WEBConfig中配置数据库连接字符串
<appSettings> <add key="ConnectionString" value="server=1.1.1.1; database=dbTest;user=test;password=test"></add> </appSettings>
取得WEbCnfig中配置的特定字符串的值：
Private strConnectString = System.Configuration.ConfigurationSettings.AppSettings.Get("ConnectPassWord")
数据库连接并返回ds：
Dim myConn As SqlConnection Dim myDataAdapter As SqlDataAdapter Dim ds As DataSet Try myConn = New SqlConnection(ConnString) myConn.Open() strSql = "select EmployeeManagementID from mstEmployeeBasic where EmployeeCode =" & txtEmployee.Text.Trim().ToString() myDataAdapter = New SqlDataAdapter(Sql, myConn) Dim ds As New DataSet myDataAdapter.Fill(ds) GetDataBase = ds If Not (ds.Tables(0).Rows.Count > 0) Then txtEmployee.Text = "" txtPassWord.Text = "" Else txtEmployee.Text = "" End If Catch ex As Exception Throw New Exception(ex.Message & "clsDatabaseAccess.GetDataBase()") Finally myConn.Close() myConn = Nothing End Try
9：后台提示信息在前台显示：
Response.Write("<script lanugage='javascript'>alert('パスワードが間違いました。');</script>")
10：后台页面跳转：
Response.Redirect("TestPaperList.aspx?code=" & StrConv(txtEmployee.Text.Trim(), VbStrConv.Narrow) & "")
11：后台取URL传过来的参数的值
employeecode = Request.QueryString("code") AdminType = Request.QueryString("type")
12:在Vb.net中 用me代替了this
Me.txtCode.Text = "" Me.txtPassword1.Text = "" Me.txtPassword2.Text = ""
13:类型转换
intCode = CInt(employeecode.Trim()) intType = CInt(AdminType.Trim)
14：拼接数据库字符串
strSql = "" strSql = strSql & "insert into " & vbCrLf strSql = strSql & " administrator values( " & vbCrLf strSql = strSql & " <$code> " & vbCrLf strSql = strSql & " ,'<$password>' " & vbCrLf strSql = strSql & " ,<$type>) " & vbCrLf strSql = Replace(strSql, "<$code>", code.ToString) strSql = Replace(strSql, "<$password>", password.Trim.Replace("'", "''")) strSql = Replace(strSql, "<$type>", type.ToString)
15：For循环块
Dim i As Integer = 0
For i = 0 To dsSelectedEmployee.Tables(0).Rows.Count - 1 lstSelected.Items(i).Text = dsSelectedEmployee.Tables(0).Rows(i)(0) & " " & dsSelectedEmployee.Tables(0).Rows(i)(1) Next
16：下拉框绑定值
Dim dsSelectedEmployee As DataSet Try If Me.dlstClass.SelectedIndex <> 0 Then dsSelectedEmployee = GetAnswerer() Me.lstSelected.DataValueField = "EmployeeNo" Me.lstSelected.DataSource = dsSelectedEmployee.Tables(0) Me.lstSelected.DataBind() Dim i As Integer = 0 For i = 0 To dsSelectedEmployee.Tables(0).Rows.Count - 1 lstSelected.Items(i).Text = dsSelectedEmployee.Tables(0).Rows(i)(0) & " " & dsSelectedEmployee.Tables(0).Rows(i)(1) Next Else Me.lstSelected.Items.Clear() End If Catch ex As Exception Response.Write(ex.Message) End Try