江南大学物联网工程学院数据库课程实验四作业4vb.net实验报告

Imports System.Data.SqlClient
Public Class Form1
'连接本机数据库并获取'test_one'数据库中的'sc'表数据
Dim mybind As BindingManagerBase
Dim myconn As New SqlConnection("Initial Catalog=test_one;Data 
Source=localhost;Integrated Security=True;")
Dim myadapter As New SqlDataAdapter("select * from sc", myconn)
Dim mydataset As New DataSet
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
myadapter.Fill(mydataset, "选课")
Me.DataGridView1.DataSource = mydataset.Tables("选课")
mybind = BindingContext(mydataset.Tables("选课"))
_display(1)
TextBox1.DataBindings.Add(New Binding("Text", mydataset, "选课.snum", True))
TextBox2.DataBindings.Add(New Binding("Text", mydataset, "选课.cnum", True))
TextBox3.DataBindings.Add(New Binding("Text", mydataset, "选课.score", True))
End Sub
Sub _display(ByVal index As Integer)
Me.TextBox1.Text = mydataset.Tables("选课").Rows(index).Item(0)
Me.TextBox2.Text = mydataset.Tables("选课").Rows(index).Item(1)
Me.TextBox3.Text = mydataset.Tables("选课").Rows(index).Item(2)
End Sub
'Button4 点击上移
Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
mybind.Position = mybind.Position - 1
_display(mybind.Position)
End Sub
'Button5 点击下移
Private Sub Button5_Click(sender As Object, e As EventArgs) Handles Button5.Click
mybind.Position = mybind.Position + 1
_display(mybind.Position)
End Sub
'Button1 点击插入数据
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim mycmd As New SqlCommand
myconn.Open()
mycmd.Connection = myconn
mycmd.CommandText = "insert into sc values('" & TextBox1.Text & "','" & 
TextBox2.Text & "'," & Val(TextBox3.Text) & ")"
MessageBox.Show(mycmd.CommandText)
Try
mycmd.ExecuteNonQuery()
Catch ex As Exception
MessageBox.Show("insert failed")
End Try
myconn.Close()
End Sub
'Button2 点击删除数据
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
mybind.RemoveAt(mybind.Position)
End Sub
'Button6 点击更新数据
Private Sub Button6_Click(sender As Object, e As EventArgs) Handles Button6.Click
Me.Validate()
mybind.EndCurrentEdit()
Dim cmd As New SqlCommandBuilder(myadapter)
myadapter.Update(mydataset.Tables("选课"))
End Sub
End Class