notacion polca visual

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

private void button1_Click(object sender, EventArgs e)
{
String exp_infija = textBox1.Text;
//StringBuilder result = new StringBuilder(exp_infija);
Not_Polaca exp = new Not_Polaca();
StringBuilder posfija = exp.ConvertPosFija(textBox1.Text);
//string result;


//result = exp.ConvertPosFija(textBox2.Text);
textBox2.Text = posfija.ToString();
}

private void button2_Click(object sender, EventArgs e)
{
String exp_infija = textBox1.Text;
Not_Polaca exp = new Not_Polaca();
StringBuilder posfija = exp.ConvertPosFija(textBox1.Text);
textBox2.Text = posfija.ToString();
textBox3.Text = exp.ResolverPosFija(textBox2.Text);


}