C# 中窗体间传值总结

对C#窗体间传值做一些总结，记录如下 :

新建Form1为父窗口，Form2为子窗口。

父窗口向子窗口传值

相对而言父窗体向子窗体传值比较容易实现。

通过重载Form2的构造函数，使其能够接受来自Form1的参数。

Form1:

private void button1_Click(object sender, EventArgs e) {
    string s = textBox1.Text;
    Form2 form2 = new Form2(s);
    form2.ShowDialog();    
}

Form2:

public Form2(String p) {
      InitializeComponent();
      label1.Text = p;
  }

通过声明全局变量

Form1:

public static string ss;
     private void button1_Click(object sender, EventArgs e) {
         ss = textBox1.Text;
         Form2 form2 = new Form2();
         form2.ShowDialog();    
     }

Form2:

private void Form2_Load(object sender, EventArgs e)
      {
          label1.Text = Form1.ss;
      }

或者

Form1:

public string Xx ;
      private void button1_Click(object sender, EventArgs e) {
          Xx = textBox1.Text;
          Form2 form2 = new Form2();
          form2.Owner = this;
          form2.ShowDialog();    
      }

Form2:

private void Form2_Load(object sender, EventArgs e)
      {
          Form1 f1 = (Form1)this.Owner;
          label1.Text = f1.Xx;
      }

通过声明公有属性

在Form2中声明公有属性，在Form1中访问公有属性，赋值。

Form2:

private string name;
    public string strinS
    {
        get {              return name;   }
        set {   name = value;   }
    }
    private void Form2_Load(object sender, EventArgs e)
    {
        label1.Text = name;
    }

Form1:

private void button1_Click(object sender, EventArgs e) {
        Form2 form2 = new Form2();
        form2.strinS = textBox1.Text;
        form2.ShowDialog();    
    }

子窗体向父窗体传值

通过委托进行传值

点击Form1的按键，跳出Form2, 当Form2子窗体的文本框内的值变化时，父窗体跟着发生变化。
Form2:

public delegate void MessageHandle(string s);
public MessageHandle messHandle;

private void textBox1_TextChanged(object sender, EventArgs e)
{
    if (messHandle != null)
    {
        messHandle(textBox1.Text.ToString());
    }
}

Form1:

private void button1_Click(object sender, EventArgs e) {
     Form2 f2 = new Form2();
     f2.messHandle = getVaule;
     f2.ShowDialog();
 }
private void getVaule(string s)
 {
     label1.Text = s;
 }

通过控件赋值

点击Form1的按键，跳出Form2, 在Form2的textbox中输入值，点击按钮，将值传入到Form1的文本框，关闭Form2。
Form1:

public partial class Form1 : Form
{
    public Form1() {
        InitializeComponent();
    }
    private void button1_Click(object sender, EventArgs e) {
        Form2 f2 = new Form2();
        f2.ShowDialog(this);  //or f2.show(this);
        // or
       //  f2.Owner = this;
      // f2.Show(); or f2.ShowDialog();           
    }
}

Form2:

public Form2() {
         InitializeComponent();
     }
     private void button1_Click(object sender, EventArgs e)
     {
         Form1 form1 = (Form1)this.Owner;
         //如果textBox 在Panel中，则需要先定位到Panel
         Panel p1 = (Panel)(form1.Controls["panel1"]);
         ((TextBox)p1.Controls["textBox1"]).Text = this.textBox1.Text;
         this.Close();
     }

通过事件进行传值

点击Form1的按键，跳出Form2, 在Form2的textbox中输入值，点击按钮，将值传入到Form1的文本框。

Form1:

public Form1() {
           InitializeComponent();
       }
       private void getVaule(Object sender, EventArgs e)
       {
           Form2 f2 = (Form2)sender;    //事件的接收者通过类型转换得到Form2的引用  
           this.textBox1.Text = f2.textValue;  // //接收到Form2的textBox1的值
       }

       private void button1_Click(object sender, EventArgs e)
       {
           Form2 f2 = new Form2();
           f2.accept += new EventHandler(getVaule);
           f2.ShowDialog();
       }

Form2 :

public Form2() {
          InitializeComponent();
      }

    public string textValue {
          get { return this.textBox1.Text;  }
          set { this.textBox1.Text = value; }
      }

      public event EventHandler accept;

      private void button1_Click(object sender, EventArgs e)
      {
          if (accept != null)
          {
              accept(this, EventArgs.Empty);  //触发事件时，传递自身引用
          }
      }