如何使用多线程在datagridview中获取数据 [英] how to use multi thread to get data in datagridview

问题描述

我如何使用多线程从数据库中获取数据并将其放入datagridview而不冻结我的应用程序，如单个Form1中的

我有datagridview和按钮和文本框，当我点击按钮时时间所有数据将同时填入datagridview如果我在文本框中键入任何内容它将被键入并且不会冻结我的应用程序



请帮帮我.. 。

解决方案

 Imports Microsoft.VisualBasic 
 Imports System 
 Imports System.Drawing 
 Imports System.Threading 
 Imports System.Windows.Forms 
 
 Friend Class CorrectMultiThreadedForm 
 Inherits Form 
 
'构造方法
 Public Sub New（）
 InitializeComponent（）
 
'创建一个文本框
 _text.Location = New Point（10,10）
 _text.Size = New Size（50,20）
 Controls.Add（_text）
 
'创建一个按钮
 bu tton.Text =Beep
 button.Size =新尺寸（50,20）
 button.Location =新点（80,10）
 
'注册Click事件处理程序
 AddHandler button.Click，AddressOf OnClick 
 
 Controls.Add（button）
 
'缓存重复使用的委托
 _enableControls = New BooleanCallback（AddressOf EnableControls）
 End Sub 
 
'按钮的Click事件调用的方法
 Private Overloads Sub OnClick（ByVal sender As Object，ByVal args As EventArgs）
'获取一个int来自字符串
 Dim _count As Int32 = 0 
尝试
 _count = Int32.Parse（_text.Text）
 Catch e1 As FormatException 
结束尝试
 
'计数到那个数字
 EnableControls（False）
 Dim回调As New WaitCallback（AddressOf Count）
 ThreadPool.QueueUserWorkItem（callback，_count）
 End Sub 
 
'异步方法每秒发出一次蜂鸣声
私有子计数（ByVal param As Object）
 
 Dim seconds As Int32 = CInt（Fix（param））
索引为Int32 = 0到秒 -  1 
 Interaction.Beep（）
 Thread.Sleep（1000）
下一个索引
 
调用（_enableControls，New Object（）{True} ）
 End Sub 
 
 Private Sub EnableControls（ByVal enable As Boolean）
 button.Enabled = enable 
 _text.Enabled = enable 
 End Sub 
 
'委托类型和匹配字段
私有委托子BooleanBallback（ByVal enable As Boolean）
私有_enableControls As BooleanCallback 
 
'一些私有字段用于引用控件
私有按钮As New Button（）
 Friend WithEvents RichTextBox1 As System.Windows.Forms.RichTextBox 
 Private _text As New TextBox（）
 
 Private Sub InitializeComponent （）
 Me.RichTextBox1 = New System.Windows.Forms.RichTextBox 
 Me.SuspendLayout（）
'
'RichTextBox1 
'
 Me.RichTextBox1.Location = New System。 Drawing.Point（12,111）
 Me.RichTextBox1.Name =RichTextBox1
 Me.RichTextBox1.Size = New System.Drawing.Size（260,139）
 Me.RichTextBox1。 TabIndex = 0 
 Me.RichTextBox1.Text =
'
'CorrectMultiThreadedForm 
'
 Me.ClientSize = New System.Drawing.Size（284,262） 
 Me.Controls.Add（Me.RichTextBox1）
 Me.Name =CorrectMultiThreadedForm
 Me.ResumeLayout（False）
 
 End Sub 
 End类

how do i use multi thread to get data from database and put it to in datagridview without freezing my Application like
in single Form1 i have datagridview and button and textbox when i click on button at that time all the data will fill in to datagridview at same time if i type anything in textbox it will be typed and not to freez my Application

Please Please Help me...

解决方案

Imports Microsoft.VisualBasic
Imports System
Imports System.Drawing
Imports System.Threading
Imports System.Windows.Forms

Friend Class CorrectMultiThreadedForm
    Inherits Form

    ' Constructor method
    Public Sub New()
        InitializeComponent()

        ' Create a text box
        _text.Location = New Point(10, 10)
        _text.Size = New Size(50, 20)
        Controls.Add(_text)

        ' Create a button
        button.Text = "Beep"
        button.Size = New Size(50, 20)
        button.Location = New Point(80, 10)

        ' Register Click event handler
        AddHandler button.Click, AddressOf OnClick

        Controls.Add(button)

        ' Cache a delegate for repeated reuse 
        _enableControls = New BooleanCallback(AddressOf EnableControls)
    End Sub

    ' Method called by the button's Click event
    Private Overloads Sub OnClick(ByVal sender As Object, ByVal args As EventArgs)
        ' Get an int from a string
        Dim _count As Int32 = 0
        Try
            _count = Int32.Parse(_text.Text)
        Catch e1 As FormatException
        End Try

        ' Count to that number
        EnableControls(False)
        Dim callback As New WaitCallback(AddressOf Count)
        ThreadPool.QueueUserWorkItem(callback, _count)
    End Sub

    ' Async method beeps once per second
    Private Sub Count(ByVal param As Object)

        Dim seconds As Int32 = CInt(Fix(param))
        For index As Int32 = 0 To seconds - 1
            Interaction.Beep()
            Thread.Sleep(1000)
        Next index

        Invoke(_enableControls, New Object() {True})
    End Sub

    Private Sub EnableControls(ByVal enable As Boolean)
        button.Enabled = enable
        _text.Enabled = enable
    End Sub

    ' A delegate type and matching field
    Private Delegate Sub BooleanCallback(ByVal enable As Boolean)
    Private _enableControls As BooleanCallback

    ' Some private fields by which to reference controls
    Private button As New Button()
    Friend WithEvents RichTextBox1 As System.Windows.Forms.RichTextBox
    Private _text As New TextBox()

    Private Sub InitializeComponent()
        Me.RichTextBox1 = New System.Windows.Forms.RichTextBox
        Me.SuspendLayout()
        '
        'RichTextBox1
        '
        Me.RichTextBox1.Location = New System.Drawing.Point(12, 111)
        Me.RichTextBox1.Name = "RichTextBox1"
        Me.RichTextBox1.Size = New System.Drawing.Size(260, 139)
        Me.RichTextBox1.TabIndex = 0
        Me.RichTextBox1.Text = ""
        '
        'CorrectMultiThreadedForm
        '
        Me.ClientSize = New System.Drawing.Size(284, 262)
        Me.Controls.Add(Me.RichTextBox1)
        Me.Name = "CorrectMultiThreadedForm"
        Me.ResumeLayout(False)

    End Sub
End Class

这篇关于如何使用多线程在datagridview中获取数据的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！