Binding.BindingComplete 事件

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

Source:

Binding.cs

在 FormattingEnabled 属性设置为 true 且完成绑定操作（如将数据从控件推到数据源或与之相反的操作）时发生。

C#

public event System.Windows.Forms.BindingCompleteEventHandler? BindingComplete;

事件类型

BindingCompleteEventHandler

示例

下面的代码示例演示如何处理 BindingComplete 事件。

C#

using System;
using System.Drawing;
using System.Windows.Forms;

class Form1 : Form
{
    private BindingSource BindingSource1 = new BindingSource();
    private TextBox textBox1 = new TextBox();
    private TextBox textBox2 = new TextBox();
    private TextBox textBox3 = new TextBox();

    public Form1()
    {
        //Set up the textbox controls.
        this.textBox1.Location = new System.Drawing.Point(82, 13);
        this.textBox1.TabIndex = 1;
        this.textBox2.Location = new System.Drawing.Point(81, 47);
        this.textBox2.TabIndex = 2;
        this.textBox3.Location = new System.Drawing.Point(81, 83);
        this.textBox3.TabIndex = 3;

        // Add the textbox controls to the form
        this.Controls.Add(this.textBox2);
        this.Controls.Add(this.textBox1);
        this.Controls.Add(this.textBox3);

        // Handle the form's Load event.
        this.Load += new System.EventHandler(this.Form1_Load);
    }
    Binding partNameBinding;
    Binding partNumberBinding;

    private void Form1_Load(object sender, EventArgs e)
    {
        // Set the DataSource of BindingSource1 to the Part type.
        BindingSource1.DataSource = typeof(Part);

        // Bind the textboxes to the properties of the Part type, 
        // enabling formatting.
        partNameBinding = textBox1.DataBindings.Add("Text",
            BindingSource1, "PartName", true);
        
        partNumberBinding = textBox2.DataBindings.Add("Text", BindingSource1, "PartNumber",
            true);

        //Bind the textbox to the PartPrice value with currency formatting.
        textBox3.DataBindings.Add("Text", BindingSource1, "PartPrice", true,
            DataSourceUpdateMode.OnPropertyChanged, 0, "C");

        // Handle the BindingComplete event for BindingSource1 and 
        // the partNameBinding.
        partNumberBinding.BindingComplete +=
            new BindingCompleteEventHandler(partNumberBinding_BindingComplete);
        partNameBinding.BindingComplete +=
            new BindingCompleteEventHandler(partNameBinding_BindingComplete);

        // Add a new part to BindingSource1.
        BindingSource1.Add(new Part("Widget", 1234, 12.45));
    }

    // Handle the BindingComplete event to catch errors and exceptions 
    // in binding process.
    void partNumberBinding_BindingComplete(object sender,
        BindingCompleteEventArgs e)
    {
        if (e.BindingCompleteState != BindingCompleteState.Success)
            MessageBox.Show("partNumberBinding: " + e.ErrorText);
    }		

    // Handle the BindingComplete event to catch errors and 
    // exceptions in binding process.
    void partNameBinding_BindingComplete(object sender,
        BindingCompleteEventArgs e)
    {
        if (e.BindingCompleteState != BindingCompleteState.Success)
            MessageBox.Show("partNameBinding: " + e.ErrorText);
    }

    [STAThread]
    static void Main()
    {
        Application.EnableVisualStyles();
        Application.Run(new Form1());
    }
}

// Represents a business object that throws exceptions when invalid values are
// entered for some of its properties.
public class Part
{
    private string name;
    private int number;
    private double price;

    public Part(string name, int number, double price)
    {
        PartName = name;
        PartNumber = number;
        PartPrice = price;
    }

    public string PartName
    {
        get { return name; }
        set
        {
            if (value.Length <= 0)
                throw new Exception("Each part must have a name.");
            else
                name = value;
        }
    }
    public double PartPrice
    {
        get { return price; }
        set { price = value; }
    }

    public int PartNumber
    {
        get { return number; }
        set
        {
            if (value < 100)
                throw new Exception("Invalid part number." +
                    " Part numbers must be greater than 100.");
            else
                number = value;
        }
    }
}

注解

当 为 true时FormattingEnabled，在以下任一条件下引发此事件：

• 数据源中的数据将推送到控件属性。

• 控件属性中的数据将推送到数据源。

此事件在完成这些操作时引发，与完成状态无关。 例如，如果绑定操作将 null 值绑定到属性 Value ，则会引发异常，但仍会发生该 BindingComplete 事件。 此事件的处理程序可以通过检查 BindingCompleteState 参数的 属性 BindingCompleteEventArgs ，根据绑定过程中的成功、错误或异常采取适当的操作。

有关处理事件的详细信息，请参阅 处理和引发事件。

适用于

另请参阅

• FormattingEnabled
• OnBindingComplete(BindingCompleteEventArgs)