TextBox1绑定的问题

2017-05-14 05:46:20 186 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

WPF中TextBox绑定变量 WPF中TextBox绑定变量为什么要将TextBox绑定到变量第一步前端TextBox绑定第二步新建绑定类第三步添加触发函数第四步绑定类添加代码第五步数据源的指定第六步绑定变量的调用为什么要将TextBox绑定到变量开发程序中TextBox是常用控件，用来显示信息，在后台代码控制中经常会对TextBox.Text属性进行修改，目的是为了让控件显示我们想要的内容，频繁修改每次都调用的话比较麻烦，也还会出现一些不必要的错误，因此，将其text属性绑定到变量，后期使用起来就十分便捷。本文提供一阅读详情



Public Class Form1

    Class BindingData

        Property A As String

    End Class



    Dim BindingDataNew As New BindingData

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

            BindingDataNew.A= 10

            TextBox1.DataBindings.Add("Text", BindingDataNew, "A", False, DataSourceUpdateMode.OnPropertyChanged)

            'BindingDataNew.BindingData = 10 '加在下面运行时不能同步显示

    End Sub



    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

            BindingDataNew.A = 999

            MsgBox(BindingDataNew.A & "-----------" & TextBox1.Text)

            '结果为   999-----------空

    End Sub

End Class

手动输入文本到TextBox1里绑定数据是同步的
但给数据赋值时并不同步显示出来和赋值到TextBox1.Text里
所以DataBindings是单向绑定吗!

...全文

【WPF】ListView 中嵌入TextBox，支持双向绑定 ListView 控件，与字符串数组，双向绑定阅读详情

im战术

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im战术 2017-05-15

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HOHO

成功了,我看晕了我试验时把其中一个


'NotifyPropertyChanged("MyText")
'它不小心被我注解了,使用它就OK了.

im战术 2017-05-15

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    Private Sub MyTB_TextChanged(sender As Object, e As EventArgs) Handles MyTB.TextChanged
        '========Sorry少加了这句========
        MyTB.MyText = MyTB.Text
        '========Sorry少加了这句========
        Text = $"数据为: {数据.Data} MyText为: {MyTB.MyText}"
    End Sub

但还是一样MyText改变不能同步Data

im战术 2017-05-15

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Imports System.ComponentModel

Public Class Form1
    Dim 数据 As New CData
    WithEvents MyTB As New MyTextBox
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        MyTB.Location = New Point(100, 100)
        Controls.Add(MyTB)
        MyTB.DataBindings.Add(New Binding("MyText", 数据, "Data", False, DataSourceUpdateMode.OnPropertyChanged))
    End Sub

    Private Sub MyTB_TextChanged(sender As Object, e As EventArgs) Handles MyTB.TextChanged
        Text = $"数据为: {数据.Data} MyText为: {MyTB.MyText}"
    End Sub

    Private Sub TextBox2_TextChanged(sender As Object, e As EventArgs) Handles TextBox2.TextChanged
        数据.Data = TextBox2.Text
        Text = $"数据为: {数据.Data} MyText为: {MyTB.MyText}"
    End Sub
End Class

Public Class MyTextBox
    Inherits TextBox
    Implements INotifyPropertyChanged

    Private _MyText As String
    Public Property MyText() As String
        Get
            Return _MyText
        End Get
        Set(ByVal value As String)
            _MyText = value
            NotifyPropertyChanged("MyText")
        End Set
    End Property


    Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged

    Public Sub NotifyPropertyChanged(ByVal propertyName As String)
        RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(propertyName))
    End Sub
End Class

Public Class CData
    Implements INotifyPropertyChanged

    Private _Data As String
    Public Property Data() As String
        Get
            Return _Data
        End Get
        Set(ByVal value As String)
            _Data = value
            NotifyPropertyChanged("Data")
        End Set
    End Property

    Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged

    Public Sub NotifyPropertyChanged(ByVal propertyName As String)
        RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(propertyName))
    End Sub
End Class

那为什么自定义添加的属性就不能同步呢! 是我哪里搞错了吗? 改数据能同步文本改文本这样的代码就不能同步数据!

xdashewan 2017-05-15

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双向时，你需要继承INotifyPropertyChanged接口，参照https://msdn.microsoft.com/zh-cn/library/system.componentmodel.inotifypropertychanged(VS.95).aspx banding时使用


textBox1.DataBindings.Add(new System.Windows.Forms.Binding("Text", 对象, "FirstName", false, DataSourceUpdateMode.OnPropertyChanged));

TextBox1绑定的问题

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