Question

我一直在使用自定义复选框控件一段时间并且发布了此问题Question...似乎问题与事件无关。

自定义控件是一个带复选框的组框。如果复选框为false，则应禁用所有组控件。这听起来很简单，但问题是当内部控件失去焦点时，会触发检查的更改事件。

经过一番挖掘后，我想我已将其缩小到将checked属性绑定到另一个对象上。当包含绑定时，它工作不正确，但删除绑定一切都按预期工作。

我现在还不确定如何解决这个问题。

有人可以帮忙吗？

以下是我的测试应用程序中的一些代码 -

表格： enter image description here

表单代码：

public partial class Form1 : Form
{
    TestProperties m_TP;

    public Form1()
    {
        // Create instance of TestProperties
        m_TP = new TestProperties();

        InitializeComponent();

        BindControls();
    }

    private void BindControls()
    {
        // Bind the values to from the controls in the group to the properties class

        // When the line below is commented out the control behaves normally
        //this.checkedGroupBox1.DataBindings.Add("Checked", m_TP, "GroupChecked");
        this.numericUpDown1.DataBindings.Add("Value", m_TP, "SomeNumber");
        this.textBox1.DataBindings.Add("Text", m_TP, "SomeText");
        this.checkBox1.DataBindings.Add("Checked", m_TP, "BoxChecked");

        // Bind the values of the properties to the lables
        this.label4.DataBindings.Add("Text", m_TP, "GroupChecked");
        this.label5.DataBindings.Add("Text", m_TP, "SomeNumber");
        this.label6.DataBindings.Add("Text", m_TP, "SomeText");
        this.label8.DataBindings.Add("Text", m_TP, "BoxChecked");
    }
}

属性存储类：

class TestProperties
{
    public bool GroupChecked { get; set; }
    public decimal SomeNumber { get; set; }
    public string SomeText { get; set; }
    public bool BoxChecked { get; set; }

    public TestProperties()
    {
        GroupChecked = false;
        SomeNumber = 0;
        SomeText = string.Empty;
        BoxChecked = true;
    }
}

修改以下是我的自定义控件的来源：

/// <summary>
/// Custom control to create a checked group box.
/// Enables / disables all controls within the group depending upon the state of the check box
/// </summary>
public class CheckedGroupBox : System.Windows.Forms.GroupBox
{
    #region Private Member Variables
    private System.ComponentModel.IContainer components = null;

    /// <summary>
    /// Checkbox to enable / disable the controls within the group
    /// </summary>
    private CheckBox chkBox;

    /// <summary>
    /// Label for the group box which is set to autosize
    /// </summary>
    private Label lblDisplay;
    #endregion

    /// <summary>
    ///  Default constructor for the control
    /// </summary>
    public CheckedGroupBox()
    {
        // This call is required by the Windows Form Designer.
        InitializeComponent();

        // The text of these controls should always be empty.
        this.Text = "";
        this.chkBox.Text = "";
    }

    #region Events & Delegates

    /// <summary>
    /// Event to forward the change in checked flag
    /// </summary>
    public event EventHandler CheckedChanged;

    /// <summary>
    /// Event to forward the change in checked state of the checkbox
    /// </summary>
    public event EventHandler CheckStateChanged;

    private void chkBox_CheckedChanged(object sender, EventArgs e)
    {
        // Disable the controls within the group
        foreach (Control ctrl in this.Controls)
        {
            if (ctrl.Name != "chkBox" && ctrl.Name != "lblDisplay")
            {
                ctrl.Enabled = this.chkBox.Checked;
            }
        }

        // Now forward the Event from the checkbox
        if (this.CheckedChanged != null)
        {
            this.CheckedChanged(sender, e);
        }
    }

    private void chkBox_CheckStateChanged(object sender, EventArgs e)
    {
        // Forward the Event from the checkbox
        if (this.CheckStateChanged != null)
        {
            this.CheckStateChanged(sender, e);
        }
    }

    #endregion

    #region Designer generated code
    /// <summary>
    /// Required method for Designer support - do not modify
    /// the contents of this method with the code editor.
    /// </summary>
    private void InitializeComponent()
    {
        this.chkBox = new System.Windows.Forms.CheckBox();
        this.lblDisplay = new System.Windows.Forms.Label();
        this.SuspendLayout();
        // 
        // chkBox
        // 
        this.chkBox.Location = new System.Drawing.Point(8, 0);
        this.chkBox.Name = "chkBox";
        this.chkBox.Size = new System.Drawing.Size(16, 16);
        this.chkBox.TabIndex = 0;
        this.chkBox.CheckStateChanged += new System.EventHandler(this.chkBox_CheckStateChanged);
        this.chkBox.CheckedChanged += new System.EventHandler(this.chkBox_CheckedChanged);
        // 
        // lblDisplay
        // 
        this.lblDisplay.AutoSize = true;
        this.lblDisplay.Location = new System.Drawing.Point(24, 0);
        this.lblDisplay.Name = "lblDisplay";
        this.lblDisplay.Size = new System.Drawing.Size(97, 13);
        this.lblDisplay.TabIndex = 1;
        this.lblDisplay.Text = "CheckedGroupBox";
        // 
        // CheckedGroupBox
        // 
        this.BackColor = System.Drawing.Color.AliceBlue;
        this.Controls.Add(this.chkBox);
        this.Controls.Add(this.lblDisplay);
        this.Size = new System.Drawing.Size(100, 100);
        this.ResumeLayout(false);
        this.PerformLayout();

    }
    #endregion

    #region Public properties

    [Bindable(true), Category("Appearance"), DefaultValue("Check Group Text")]
    public override string Text
    {
        get{ return this.lblDisplay.Text; }
        set{ this.lblDisplay.Text = value; }
    }

    [Bindable(true), Category("Appearance"), DefaultValue("Checked")]
    public System.Windows.Forms.CheckState CheckState
    {
        get{ return this.chkBox.CheckState; }
        set
        { 
            this.chkBox.CheckState = value; 

            foreach( Control ctrl in this.Controls )
            {
                if( ctrl.Name != "chkBox" && ctrl.Name != "lblDisplay" )
                {
                    ctrl.Enabled = this.chkBox.Checked;
                }
            }
        }
    }

    [Bindable(true), Category("Appearance"), DefaultValue("True")]
    public bool Checked
    {
        get{ return this.chkBox.Checked; }
        set
        { 
            this.chkBox.Checked = value; 

            foreach( Control ctrl in this.Controls )
            {
                if( ctrl.Name != "chkBox" && ctrl.Name != "lblDisplay" )
                {
                    ctrl.Enabled = this.chkBox.Checked;
                }
            }
        }
    }

    [Bindable(true), Category("Behavior"), DefaultValue("False")]
    public bool ThreeState
    {
        get{ return this.chkBox.ThreeState; }
        set{ this.chkBox.ThreeState = value; }
    }

    #endregion

}

Answer 1

您需要更改BindControls方法，如下所示。原因是默认情况下控件正在更新以反映m_TP的属性，但是当它们的值发生更改时，更改不会反映在m_TP中（我想Leave事件会导致控件重新绑定到它们的数据源）。通过添加DataSourceUpdateMode参数，可以双向进行更改。

private void BindControls()
{
    // Bind the values to from the controls in the group to the properties class

    // When the line below is commented out the control behaves normally
    this.checkedGroupBox1.DataBindings.Add("Checked", m_TP, "GroupChecked", false, DataSourceUpdateMode.OnPropertyChanged);
    this.numericUpDown1.DataBindings.Add("Value", m_TP, "SomeNumber", false, DataSourceUpdateMode.OnPropertyChanged);
    this.textBox1.DataBindings.Add("Text", m_TP, "SomeText", false, DataSourceUpdateMode.OnPropertyChanged);
    this.checkBox1.DataBindings.Add("Checked", m_TP, "BoxChecked", false, DataSourceUpdateMode.OnPropertyChanged);

    // Bind the values of the properties to the lables
    this.label4.DataBindings.Add("Text", m_TP, "GroupChecked");
    this.label5.DataBindings.Add("Text", m_TP, "SomeNumber");
    this.label6.DataBindings.Add("Text", m_TP, "SomeText");
    this.label8.DataBindings.Add("Text", m_TP, "BoxChecked");
}

Answer 2

首先，为了使绑定正常工作，您需要在属性存储类上实现INotifyPropertyChanged。请参阅示例here

在Visual Studio环境中，创建一个指向“Object”类型的新DataSource。选择TestProperties类作为源对象（如果类未显示在列表中，请确保已构建包含程序集，并且WinForm项目具有对它的引用）。

Data Source Configuration Wizard

现在，将BindingSource从工具箱拖到自定义控件上。将BindingSource的DataSource属性设置为您在上一步中创建的TestProperties数据源。

现在，选择自定义控件组框并转到（DataBindings）部分。单击高级字段中的“...”。将自定义网格控件的“已启用”属性绑定到BindingSource的“BoxChecked”属性。这一切都可以在设计师中完成（或者如果您愿意，可以通过代码完成）

enter image description here

通过BindingSource将自定义控件上的其他WinForms元素绑定到TestProperties类的相应元素。

现在，在自定义控件上公开一个属性，以便您可以在“父”窗体中绑定它。确保将BindingSource的“DataSource”设置为新的引用属性。

    private TestProperties _properties;
    public TestProperties Properties
    {
        get { return _properties; }
        set
        {
            _properties = value;
            this.bindingSource1.DataSource = _properties;
        }
    }

    public UserControl1()
    {
        InitializeComponent();
    }

在托管控件的父窗体中，您有几个选项。

1）您可以直接执行UserControl公开的TestProperties类的绑定，就像在上面的例子中一样

2）您可以重复用于在父控件上的用户控件上设置绑定的BindingSource练习，并将新BindingSource的DataSource属性（在父窗体上）设置为等于UserControl的公开TestProperties属性。

Answer 3

像这样的东西尽可能接近：

enter image description here

我显然没有groupbox的代码（包括复选框）所以我尽我所能。

这可以通过将其添加到顶部复选框来实现：

private void checkBox1_CheckedChanged(object sender, EventArgs e)
{
   groupBox1.Enabled = ((CheckBox)(sender)).Checked;
}

我也重新启用了这一行：

this.checkBox1.DataBindings.Add("Checked", m_TP, "GroupChecked");

如何绑定自定义控件复选框

3 个答案: