VB数据库应用程序开发演示.docx

1、VB数据库应用程序开发演示一、 新建项目二、设计登录窗体代码如下：Imports System 引入数据库操作类命名空间Imports System.DataImports System.Data.SqlClientPublic Class 登录 Dim i As Integer = 3 声明计数器i，用来记录登录次数 Dim strsql As String Dim strconn As String Dim objcommand As SqlClient.SqlCommand Dim objdr As SqlClient.SqlDataReader Dim str1, str2 As St

2、ring 取消按钮事件 Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click TextBox1.Text = TextBox2.Text = TextBox1.Focus() End Sub 确定按钮事件，控制登录 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click str

3、conn = data source=HD30-A1;initial catalog=xscj;user id=sa;password=123456; strsql = select 用户名,密码 from users objcommand = New SqlClient.SqlCommand(strsql, New SqlClient.SqlConnection(strconn) objcommand.Connection.Open() objdr = objcommand.ExecuteReader(CommandBehavior.CloseConnection) With objdr D

4、o While .Read = True str1 = .GetString(0) str2 = .GetString(1) If Trim(TextBox1.Text) = Trim(str1) And Trim(TextBox2.Text) = Trim(str2) Then MessageBox.Show(恭喜您登录成功！, 系统提示, MessageBoxButtons.OK, MessageBoxIcon.Information) main.Show() Me.Visible = False Exit Sub End If Loop End With i = i - 1 If i =

5、 0 Then MessageBox.Show(您已经没有登录机会了，再见！, 系统提示, MessageBoxButtons.OK, MessageBoxIcon.Hand) Me.Close() Else MessageBox.Show(登录失败！ + 您还有 + Str(i) + 次登录机会！, 系统提示, MessageBoxButtons.OK, MessageBoxIcon.Error) TextBox1.Text = TextBox2.Text = TextBox1.Focus() End If End SubEnd Class运行结果三、设计主窗体主窗体代码如下：Private

6、 Sub 学生信息查询ToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles 学生信息查询ToolStripMenuItem.Click xscx.MdiParent = Me xscx.Show() End Sub Private Sub 学生信息修改ToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles 学生信息修改ToolStripMe

7、nuItem.Click xsxg.MdiParent = Me xsxg.Show() End Sub Private Sub 主窗体_Disposed(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Disposed login.Close() End Sub Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick ToolStripStatusLabel1.T

8、ext = Now End Sub Private Sub ToolStripMenuItem3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ToolStripMenuItem3.Click Dim i As Integer i = MsgBox(是否退出学生成绩管理系统？, MsgBoxStyle.OkCancel, 提示) If i = 1 Then End Else Exit Sub End IfEnd Sub运行结果四、查询窗体设计Dim strconn As String = da

9、ta source=cheng;initial catalog=xscj;user id=sa;password=123456; Dim objds As New Data.DataSet Dim objda As SqlClient.SqlDataAdapter Dim bingpage As BindingManagerBase Dim strsql As String 窗体加载事件，将数据绑定到指定的对象 Private Sub 学生信息查询_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles

10、MyBase.Load strsql = select * from xs objda = New SqlClient.SqlDataAdapter(strsql, strconn) objda.Fill(objds, xs) DataGridView1.DataSource = objds.Tables(xs) bingpage = Me.BindingContext(objds, xs) TextBox1.DataBindings.Add(New Binding(text, objds, 学号) TextBox2.DataBindings.Add(New Binding(text, obj

11、ds, 姓名) TextBox3.DataBindings.Add(New Binding(text, objds, 性别) DateTimePicker1.DataBindings.Add(New Binding(text, objds, 出生时间) TextBox5.DataBindings.Add(New Binding(text, objds, 专业名) TextBox4.DataBindings.Add(New Binding(text, objds, 总学分) RichTextBox1.DataBindings.Add(New Binding(text, objds, xs.备注)

12、 ComboBox1.Items.Add(学号) ComboBox1.Items.Add(姓名) ComboBox1.Items.Add(专业名) End Sub 首记录按钮事件 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click bingpage.Position = 1 Button1.Enabled = False Button2.Enabled = False Button3.Enabled = True Button4.E

13、nabled = True End Sub 上一条记录按钮事件 Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click bingpage.Position = bingpage.Position - 1 If bingpage.Position 1 Then Button1.Enabled = True Button2.Enabled = True Button3.Enabled = True Button4.Enabled = Tru

14、e Else Button1.Enabled = False Button2.Enabled = False Button3.Enabled = True Button4.Enabled = True End If End Sub 下一条记录按钮事件 Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click bingpage.Position = bingpage.Position + 1 If bingpage.Position bin

15、gpage.Count - 1 Then Button1.Enabled = True Button2.Enabled = True Button3.Enabled = True Button4.Enabled = True Else Button1.Enabled = True Button2.Enabled = True Button3.Enabled = False Button4.Enabled = False End If End Sub 尾记录按钮事件 Private Sub Button4_Click(ByVal sender As System.Object, ByVal e

16、As System.EventArgs) Handles Button4.Click bingpage.Position = bingpage.Count - 1 Button1.Enabled = True Button2.Enabled = True Button3.Enabled = False Button4.Enabled = False End Sub 条件查询按钮事件 Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click

17、 objds.Clear() If ComboBox1.Text = Or TextBox9.Text = Then MessageBox.Show(请输入查询条件！) Exit Sub Else strsql = select * from xs where & Trim(ComboBox1.Text) & = & & Trim(TextBox9.Text) & objda = New SqlClient.SqlDataAdapter(strsql, strconn) objda.Fill(objds, xs) DataGridView1.DataSource = objds.Tables(

18、xs) End If End Sub 显示所有记录按钮事件 Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click objds.Clear() strsql = select * from xs objda = New SqlClient.SqlDataAdapter(strsql, strconn) objda.Fill(objds, xs) DataGridView1.DataSource = objds.Tables(xs) En

19、d SubEnd Class五、修改子窗体Public Class 学生信息修改 Inherits System.Windows.Forms.Form Dim strconn As String = data source=cheng;initial catalog=学生成绩管理;user id=sa;password=123456; Dim objds As New Data.DataSet Dim objda As SqlClient.SqlDataAdapter Dim bingpage As BindingManagerBase Dim cn As New SqlClient.SqlC

20、onnection Dim cmd As SqlClient.SqlCommand Private Sub 学生信息修改_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load ComboBox1.Items.Add(男) ComboBox1.Items.Add(女) Dim strsql As String strsql = select * from 学生表 objda = New SqlClient.SqlDataAdapter(strsql, strconn) objda.

21、Fill(objds, 学生表) DataGridView1.DataSource = objds.Tables(学生表) bingpage = Me.BindingContext(objds, 学生表) Dim i As Integer For i = 1970 To 2000 ComboBox2.Items.Add(i) Next For i = 1 To 12 ComboBox3.Items.Add(i) Next For i = 1 To 31 ComboBox4.Items.Add(i) Next End Sub Private Sub Button1_Click(ByVal sen

22、der As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Button1.Enabled = False Button2.Enabled = True TextBox1.ReadOnly = False TextBox2.ReadOnly = False TextBox3.ReadOnly = False RichTextBox1.ReadOnly = False End Sub Private Sub Button2_Click(ByVal sender As System.Object, ByVal e

23、 As System.EventArgs) Handles Button2.Click Button1.Enabled = True Dim sql, d As String d = ComboBox2.Text & - & ComboBox3.Text & - & ComboBox4.Text sql = insert into 学生表(学号,姓名,性别,院系名称,出生日期,备注) values( & Trim(TextBox1.Text) & , & _ Trim(TextBox2.Text) & , & Trim(ComboBox1.Text) & , & Trim(TextBox3.T

24、ext) & , & CStr(d) & , & _ Trim(RichTextBox1.Text) & ) cn.ConnectionString = strconn cn.Open() cmd = New SqlClient.SqlCommand(sql, cn) cmd.ExecuteNonQuery() cmd.Dispose() cn.Dispose() Button1.Enabled = True Button2.Enabled = False End Sub Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click DataGridView1.ReadOnly = False End Sub Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click DataGridView1.ReadOnly = True objda.Update(objds) End SubEnd Class