Set value to another form

Question

I have to form Form1 and Form2

Form1 source

namespace WindowsFormsApplication1
{
    public partial class Form1 :          


        

Answer 1

Use Constructor method , here is example

In form2

public Form2(string strTextBox)
{
 InitializeComponent(); 
 label1.Text=strTextBox;
}

In form1 click event

private void label1_Click(object sender, System.EventArgs e)
{
Form2 frm=new Form2(textBox1.Text);
frm.Show();
}

For more information , reference Passing Data Between Forms !

Answer 2

public partial class Form1 : Form
{
public Form1() {
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e){
Form2 frm = new Form2(this);
frm.Show();
}
}
public partial class Form2 : Form
{
Form _frm;
public Form2(Form frm)
{
_frm = frm;
InitializeComponent();
}`enter code here`

private void button1_Click(object sender, EventArgs e)
{
Form1 formVariable = (Form1)_frm;
formVariable.textBox.Text = "Hello";
}
}

Answer 3

You need to pass a reference to your Form1 instance to the Form2 instance.

You can do that like this:

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void label1_Click(object sender, EventArgs e)
        {
            Form2 frm = new Form2(this); // <---- Pass a reference to this form to Form2
            frm.SetBtn = "teste test";
            frm.Show();
        }

        public string setLb
        {
            set
            {
                label1.Text = value;
            }
        }
    }
}

And you would need to change the Form2 implementation a little aswell:

namespace WindowsFormsApplication1
{
    public partial class Form2 : Form
    {
        private Form1 other;

        //Empty constructor for the designer
        public Form2()
        {
            InitializeComponent();
        }

        public Form2(Form1 other)
        {
            this.other = other;
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            other.setLb = "test test";
        }

        public string SetBtn
        {
            set
            {
                button1.Text = value;
            }
        }
    }
}

Answer 4

In Form2 you have to add a parameter for the Form1.

i.e.

// Form1
...
private void button1_Click(object sender, EventArgs e)
{
    Form2 frm = new Form2(this);
    frm.SetBtn = "teste test";
    frm.Show();
}
...

// Form2
public Form2(Form frm1)
{
    InitializeComponent();
    frm1.setLb = "test test";
}