vb.net 数据网格视图刷新

vb.net Data Gridview REfresh

提问by OneNathan

i am having some issues updating a table that i have in a VB.net Windows Forms in VS 2012

我在更新 VS 2012 中的 VB.net Windows 窗体中的表时遇到了一些问题

i have setup the database from a service Data base, it just need a small amount of data stored locally

我已经从服务数据库设置了数据库，它只需要本地存储的少量数据

what i am trying to do when i create a new user it update the data grid view

当我创建一个新用户时我想做什么它会更新数据网格视图

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    BDate1.Format = DateTimePickerFormat.Custom
    BDate1.CustomFormat = "MM/dd/yyyy"

    If fname.Text <> "" And lname.Text <> "" Then
        If Not cn.State = ConnectionState.Open Then
            cn.Open()
        End If
        ' cn1.Open()
        If rb1.Checked Then
            gen = rb1.Text.ToString
        ElseIf rb2.Checked Then
            gen = rb2.Text.ToString
        End If

        cmd.CommandText = "INSERT INTO StudentTB (FirstName,LastName,Birthday,Avatar,Gender,Grade) values('" & fname.Text & "', '" & lname.Text & "', '" & BDate1.Text & "', '" & AvtarNM.Text & "', '" & gen & "', '" & TxtGrade.Text & "')"
        Dim dt As New DataTable
        dt.Load(cmd.ExecuteReader())
        DataGridView1.DataSource = dt
        ' cmd.ExecuteNonQuery()
        cn.Close()
        fname.Text = ""
        lname.Text = ""

the issue is that i can clear the table and reload it with button but it does not show the updated values with out closing the application then reopening it, i have tried a few thing and nothing seems to refresh the connection and or update the database. any help would help.

问题是我可以清除表格并使用按钮重新加载它，但它不显示更新的值而无需关闭应用程序然后重新打开它，我尝试了一些事情，但似乎没有任何东西可以刷新连接和或更新数据库。任何帮助都会有所帮助。

thanks

谢谢

Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click

    'DataGridView1.DataSource = Nothing
     Database1DataSet1.StudentTB.Clear()
    ' Database1DataSet1.refresh()
    ' Dim myda As String
    '  cmd.Dispose()
    ' cmd.Connection = cn
    'Me.Database1DataSet1.Clear()
     Me.StudentTBTableAdapter.Fill(Me.Database1DataSet1.StudentTB)
    '  'myda = New SqlDataAdapter(cmd)


End Sub

here is the full code

这是完整的代码

    Imports System
Imports System.Data
Imports System.Data.SqlClient
Imports System.Data.SqlClient.SqlDataReader
Imports System.Windows.Forms

Public Class Student

    Dim cn As New SqlConnection("Data Source=(LocalDB)\v11.0;AttachDbFilename=C:\Users\Nate\documents\visual studio 2012\Projects\WindowsApplication9\WindowsApplication9\Database1.mdf;Integrated Security=True")
    Dim cmd As New SqlCommand
    Dim dr As SqlDataReader
    Private dataAdapter As New SqlDataAdapter()
    Dim gen As String
    Dim bs As New BindingSource
    Dim dt As New DataTable

    Private Sub Student_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        'TODO: This line of code loads data into the 'Database1DataSet1.avTable' table. You can move, or remove it, as needed.
        Me.AvTableTableAdapter.Fill(Me.Database1DataSet1.avTable)
        'TODO: This line of code loads data into the 'Database1DataSet1.StudentTB' table. You can move, or remove it, as needed.
        Me.StudentTBTableAdapter.Fill(Me.Database1DataSet1.StudentTB)
        cmd.Connection = cn
        Form1.Hide()



    End Sub

    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        If AvTableBindingSource.Position + 1 < AvTableBindingSource.Count Then
            AvTableBindingSource.MoveNext()
            Button7.PerformClick()
            ' Otherwise, move back to the first item.
        Else
            AvTableBindingSource.MoveFirst()
            Button7.PerformClick()
        End If

        ' Force the form to repaint.
        Me.Invalidate()



    End Sub


    Private Sub Button7_Click(sender As Object, e As EventArgs) Handles Button7.Click
        PictureBox1.Image = System.Drawing.Bitmap.FromFile(ID.Text)
    End Sub


    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        BDate1.Format = DateTimePickerFormat.Custom
        BDate1.CustomFormat = "MM/dd/yyyy"

        If fname.Text <> "" And lname.Text <> "" Then
            If Not cn.State = ConnectionState.Open Then
                cn.Open()
            End If
            ' cn1.Open()
            If rb1.Checked Then
                gen = rb1.Text.ToString
            ElseIf rb2.Checked Then
                gen = rb2.Text.ToString
            End If

            cmd.CommandText = "INSERT INTO StudentTB (FirstName,LastName,Birthday,Avatar,Gender,Grade) values('" & fname.Text & "', '" & lname.Text & "', '" & BDate1.Text & "', '" & AvtarNM.Text & "', '" & gen & "', '" & TxtGrade.Text & "')"
            cmd.ExecuteNonQuery()
            dt.Load(cmd.ExecuteReader())
            bs.DataSource = dt
            DataGridView1.DataSource = bs
            cn.Close()
            fname.Text = ""
            lname.Text = ""




        End If
    End Sub
    Private Sub genPCI()
        If rb1.Checked Then
            gen = rb1.Text.ToString
        ElseIf rb2.Checked Then
            gen = rb2.Text.ToString
        End If
    End Sub

    Public Function ChangeFormat(ByVal dtm As DateTime, ByVal format As String) As String
        Return dtm.ToString(format)
    End Function



    Private Sub Closestudent_Click(sender As Object, e As EventArgs) Handles Closestudent.Click
        Form1.Show()
        Me.Close()
    End Sub

    Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
        bs.EndEdit()
        dataAdapter.Update(dt)
        DataGridView1.DataSource = dt

        ' dt.Load(Command.ExecuteReader())
        'Database1DataSet1.Reset()
        'DataGridView1.Columns.Clear()
        ' DataGridView1.DataSource = Nothing
        ' Me.StudentTBTableAdapter.Fill(Me.Database1DataSet1.StudentTB)
        ' StudentTBBindingSource.ResetBindings(True)
        ' Database1DataSet1.refresh()
        ' Dim myda As String
        '  cmd.Dispose()
        ' cmd.Connection = cn
        ' StudentTBBindingSource.ResetBindings(False)
        'Database1DataSet1.StudentTB.Clear()

        '  'myda = New SqlDataAdapter(cmd)

        ' DataGridView1.DataSource = Database1DataSet1.StudentTB
    End Sub


End Class

回答by matzone

You can try like this

你可以这样试试

Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click

    bs.EndEdit()
    dataadapter.Update(dt)
    DataGridView1.DataSource = dt

End Sub

UPDATE

更新

or you can use bindingdatasource and delare it on your form class

或者您可以使用 bindingdatasource 并在您的表单类中使用它

Dim bs As New BindingSource

and in datagridview .. in button1_click

并在 datagridview .. 在 button1_click

Dim dt As New DataTable
dt.Load(cmd.ExecuteReader())
bs.DataSource = dt
DataGridView1.DataSource = bs

So, if updated then will show after button4_click

因此，如果更新，则将在 button4_click 后显示

回答by Kasnady

    Datagridview1.datasource = nothing
Dataset.reset
dim cmd as new sqldataadapter
cmd = "SELECT * FROM YOUR_DATABSE", con
con.open
cmd.fill(Dataset)
datagridview1.datasource = dataset(0).defaultview

Add these code to you button insert

将这些代码添加到您的按钮插入

回答by OneNathan

okay after a lot of playing around this seem to fix my issue http://msdn.microsoft.com/en-us/library/fbk67b6z.aspxwell all i can say it is working no idea why but it works.

好吧，经过大量的尝试，这似乎解决了我的问题http://msdn.microsoft.com/en-us/library/fbk67b6z.aspx好吧，我只能说它正在工作，不知道为什么，但它有效。

Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click

    Me.DataGridView1.DataSource = Me.StudentTBBindingSource
    GetData("select * from StudentTB")

End Sub

Private Sub GetData(ByVal selectCommand As String)

    Try
        ' Specify a connection string. Replace the given value with a  
        ' valid connection string for a Northwind SQL Server sample 
        ' database accessible to your system. 
        Dim connectionString As String = "Data Source=(LocalDB)\v11.0;AttachDbFilename=C:\Users\Nate\documents\visual studio 2012\Projects\WindowsApplication9\WindowsApplication9\Database1.mdf;Integrated Security=True"


        ' Create a new data adapter based on the specified query. 
        Me.dataAdapter = New SqlDataAdapter(selectCommand, connectionString)

        ' Create a command builder to generate SQL update, insert, and 
        ' delete commands based on selectCommand. These are used to 
        ' update the database. 
        Dim commandBuilder As New SqlCommandBuilder(Me.dataAdapter)

        ' Populate a new data table and bind it to the BindingSource. 
        Dim table As New DataTable()
        table.Locale = System.Globalization.CultureInfo.InvariantCulture
        Me.dataAdapter.Fill(table)
        Me.StudentTBBindingSource.DataSource = table

        ' Resize the DataGridView columns to fit the newly loaded content. 
        ' Me.DataGridView1.AutoResizeColumns( _
        '  DataGridViewAutoSizeColumnsMode.AllCellsExceptHeader)
    Catch ex As SqlException
        MessageBox.Show("To run this example, replace the value of the " + _
            "connectionString variable with a connection string that is " + _
            "valid for your system.")
    End Try

End Sub

回答by Akon_Harshan

By Using ComboBox To Search

通过使用 ComboBox 进行搜索

sql = " select * from english_language where lang=' " & ComboBox2.Text & " ' "   

da = New OleDb.OleDbDataAdapter(sql, con)

Dim dt As New DataTable
da.Fill(dt)
DataGridView1.DataSource = dt
DataGridView1.Refresh()

回答by Dimuth De Zoysa

Try this code to btnClear.

试试这个代码到 btnClear。

DataGridView.DataSource = 0

Press clear button. After that click the reload button that you coded.

按清除按钮。之后单击您编码的重新加载按钮。

I think it will reset and reload the data in data grid view.

我认为它会在数据网格视图中重置并重新加载数据。