窗体Form1和Form2 传值

背景：窗体Form1和Form2 Form2由Form1打开（1、模式窗体 2、非模式）
要求：Form2的TextBox值传回Form1的TextBox中
方法：情况一：（模式窗体）Form1 .ShowDialog（）打开Form2view plaincopy to clipboardprint?
Form1：   public partial class Form1 : Form   {   public Form1()   {   InitializeComponent();   }   private void button1_Click(object sender, EventArgs e)   {   Form2 frm = new Form2(this,textBox1.Text);//带参数构造Form2(此方法该处带俩参数构造多余)   if (frm.ShowDialog() == DialogResult.OK)   {   this.textBox1.Text += frm.ReturnText;//通过Form2的属性获得回传值   }   frm = null;   }   Form2：   public partial class Form2 : Form   {   private Form1 pfrm;   private string frm1txt;   public Form2(Form1 parentfrm,string frm1text)   {   InitializeComponent();   pfrm = parentfrm;   frm1txt = frm1text;   }   public string ReturnText//回传值的属性   {   get { return this.frm1txt; }   }   private void button2_Click(object sender, EventArgs e)//给属性赋值并关闭模式窗体Form2   {   frm1txt = this.textBox2.Text;   this.DialogResult = DialogResult.OK;//*必加 模式窗体打开后 只有DialogResult初始化后才可继续操作 否则值无法传回   this.Close();//模式窗体关闭.close（）相当于将窗体隐藏 彻底关闭需要用.Dispose（）   }   private void button3_Click(object sender, EventArgs e)//关闭   {   this.DialogResult = DialogResult.Cancel;//同*   this.Close();   }  Form1：public partial class Form1 : Form{public Form1(){InitializeComponent();}private void button1_Click(object sender, EventArgs e){Form2 frm = new Form2(this,textBox1.Text);//带参数构造Form2(此方法该处带俩参数构造多余)if (frm.ShowDialog() == DialogResult.OK){this.textBox1.Text += frm.ReturnText;//通过Form2的属性获得回传值}frm = null;}Form2：public partial class Form2 : Form{private Form1 pfrm;private string frm1txt;public Form2(Form1 parentfrm,string frm1text){InitializeComponent();pfrm = parentfrm;frm1txt = frm1text;}public string ReturnText//回传值的属性{get { return this.frm1txt; }}private void button2_Click(object sender, EventArgs e)//给属性赋值并关闭模式窗体Form2{frm1txt = this.textBox2.Text;this.DialogResult = DialogResult.OK;//*必加 模式窗体打开后 只有DialogResult初始化后才可继续操作 否则值无法传回this.Close();//模式窗体关闭.close（）相当于将窗体隐藏 彻底关闭需要用.Dispose（）}private void button3_Click(object sender, EventArgs e)//关闭{this.DialogResult = DialogResult.Cancel;//同*this.Close();} 情况二：（非模式窗体）Form1 .Show（）打开Form2view plaincopy to clipboardprint?Form1：   public partial class Form1 : Form   {   public Form1()   {   InitializeComponent();   }   private void button1_Click(object sender, EventArgs e)   {   Form2 frm = new Form2(this,textBox1.Text);    //带参数构造Form2（此处参数1必须，参数2多余 参数2作用为将Form1的值传递到Form2）   frm.Show();   }   public void ChangeText(string str)//获得Form2回传过来的值   {   this.textBox1.Text += str;   }   }   Form2:   public partial class Form2 : Form   {   private Form1 pfrm;   private string frm1txt;   public Form2(Form1 parentfrm,string frm1text)   {   InitializeComponent();   pfrm = parentfrm;   frm1txt = frm1text;   }   
}   
private void button1_Click(object sender, EventArgs e)   {   pfrm.ChangeText(this.textBox2.Text);//调用Form1的方法   }   
private void button4_Click(object sender, EventArgs e)   {   pfrm.textBox1.Text += "sdfsdfsd";//或直接访问Form1的控件   }