C# 委托说明与解释

委托就是一个函数声明,但没有函数体,可以使它引用不同的函数来实现不同的目的,将真正的事情交给其它人处理。
最简单的方式见下:
例1:

private void button3_Click(object sender, EventArgs e)
        {
            Set set_deg = new Set(set2);
            set_deg(80);
        }
        public void set2(int value)
        {
            progressBar1.Value = value; 
        }

例2:

public delegate string rename(string name);
        public string get_rename(rename rename,string name)
        {
            return "final name:" + rename(name);
        }
        public string test(string name)
        {
            return "rename:"+name;
        }
        private void button7_Click(object sender, EventArgs e)
        {
            rename rename=new rename(test);
            string final_name = get_rename(rename, "刘洪方");
            MessageBox.Show(final_name);
        }

当在使用多线程场景时,需要使用invoke来让控制所在窗口的线程调用委托,实现方式见下:

public void set(int value)
        {
            progressBar1.Value = value;
        }
private void button2_Click(object sender, EventArgs e)
        {
            ThreadStart ts = new ThreadStart(run);
            Thread thread = new Thread(ts);
            thread.Start();
        }
public void run()
        {
            for (int i = 1; i <= 100; i++)
            {
                Thread.Sleep(100);
                if (this.InvokeRequired)
                {
                    Set set_deg = new Set(set);
                    this.Invoke(set_deg, new object[] { i });
                }
                else
                {
                    set(i);
                }                
            }
        }
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转载自blog.csdn.net/chscomfaner/article/details/103729882