take 2 forms form1.cs and form2.cs with one textbox on each forms and then change the modifier property of the textbox on each form from private to public add a button to form1.cs generate its click event by double clicking the button on form1 and then add in the following code in the click event of the button
Form2 obj = new Form2();
obj.textbox1.Text = this.textbox1.Text;
obj.Show();
this.Hide();
and then run the application
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Thanks & Regards
Radix :rose: