Question

我有一个按钮，我必须调用Gridview事件，任何人都可以帮助我如何实现此功能。我的代码如下能做什么？

DataGridViewTextBoxColumn col1 = new DataGridViewTextBoxColumn();
DataGridViewTextBoxColumn col2 = new DataGridViewTextBoxColumn();
DataGridViewTextBoxColumn col3 = new DataGridViewTextBoxColumn();
col1.HeaderText = "Variance";
col2.HeaderText = "Tolerance";
col3.HeaderText = "Flags";

if (e.ColumnIndex == 5 || e.ColumnIndex == 6)
{
    double  ActualWeight;
    double TargetWeight;

    object val1 = dataGridView2.Rows[e.RowIndex].Cells[5].Value;
    object val2 = dataGridView2.Rows[e.RowIndex].Cells[6].Value;

    if (val1 != null && val2 != null
      && double.TryParse(val1.ToString(), out ActualWeight)
      && double.TryParse(val2.ToString(), out TargetWeight))
    {
        dataGridView2.Rows[e.RowIndex].Cells[0].Value =Math.Round (ActualWeight-TargetWeight);
    }
    else
    {
        dataGridView2.Rows[e.RowIndex].Cells[0].Value =         "Invalid Numbers";
    }       
}


protected void bUpdate_Click(object sender, EventArgs e)
{
   // I have to call Gridview Event here
}

Answer 1

您无法提出其他课程事件。事件实际上是作为私人代表编写的。但您可以通过反射或控制继承来实现。

在Control Inheritance中，您必须首先从目标控件（DataGridView）继承，然后定义一个方法来调用您需要运行它的Event。

换句话说，您只需找到私有委托字段，获取它，然后调用它：

public static void Raise<TEventArgs>(this object source, string eventName, TEventArgs eventArgs) where TEventArgs : EventArgs
    {
        var eventDelegate = (MulticastDelegate)source.GetType().GetField(eventName, BindingFlags.Instance | BindingFlags.NonPublic).GetValue(source);
        if (eventDelegate != null)
        {
            foreach (var handler in eventDelegate.GetInvocationList())
            {
                handler.Method.Invoke(handler.Target, new object[] { source, eventArgs });
            }
        }
    }

参考文献：

The following code example shows how to load an assembly, create an instance of a type from the assembly, create an event handler using a dynamic assembly, and hook up the dynamic event handler. All actions are performed using late binding.

How to: Hook Up a Delegate Using Reflection

How do I raise an event via reflection in .NET/C#?

Answer 2

例如，我按名称 MySharedClass 创建了一个静态类：

using System.Reflection;

namespace WindowsFormsApplication1
{
    public static class MySharedClass
    {
        public static void Raise<TEventArgs>(this object source, string eventName, TEventArgs eventArgs) where TEventArgs : EventArgs
        {
            var eventDelegate = (MulticastDelegate)source.GetType().GetField(eventName, BindingFlags.Instance | BindingFlags.NonPublic).GetValue(source);
            if (eventDelegate != null)
            {
                foreach (var handler in eventDelegate.GetInvocationList())
                {
                    handler.Method.Invoke(handler.Target, new object[] { source, eventArgs });
                }
            }
        }
    }
}

然后，在视图层代码中，例如在按钮上单击事件会引发：

private void button1_Click(object sender, EventArgs e)
    {
        dataGridView1.Raise("Click", new EventArgs());
    }

如何调用Gridview单元格单击“按钮”中的“事件”

2 个答案: