Winform form窗体已弹出框的形式出现并回传值

From2（弹出框）回传数据到From1 

Form1(数据接收form):

public string Sstr;

private void button1_Click(object sender, EventArgs e)

{

Form2 form= new Form2();

form.ShowDialog();

if (form.DialogResult == DialogResult.OK)

{

Sstr = form.Cstr;

}

}

Form2(回传数据的form):

public string Cstr;

private void button1_Click(object sender, EventArgs e)

{

Cstr= label.Text;

this.DialogResult = DialogResult.OK;

}