TextBox problem 1

I have :

textbox1 , textbox2, buton 1

and make buton 1 event .

I run the program . Iwant put mark "I" in to textbox1

in order to in textbox2 show me mark "I" by putting buton 1 .

how make string in text box ; how lead out string in text box ?
how compare string as "I" , "-"
how use in simply problem , if then else instruction ?

i use :

textBox1->Text;

if textBox1->Text="I"

textBox2->Text="I";

else

textBox2->Text="-";

1>c:\users\rb\documents\visual studio 2005\projects\stacja\stacja\Form1.h(134) : error C2061: syntax error : identifier 'textBox1'

1>c:\users\rb\documents\visual studio 2005\projects\stacja\stacja\Form1.h(136) : error C2181: illegal else without matching if

String^ textBox1=Text;

if (textBox1="I")

textBox2->Text="I";

else

textBox2->Text="-";

and then i have only "I" in textBox2 , always"I" ; I would like "-" when i push buton and write other letter than"I" in textBox1 .