How can i use the ASCII code for a keyboard key F5 in a "KeyPressEventHandler"

Question

The code below show the content of a variavel in a COMBOBOX when the user pressures keyboard key ESC. I would like to use the ASCII code for a keyboard key F5. The ASCII code is 116 but when i substitute then it does not function. How can i make execute the code with the F5 keyboard key? private void Ultdeterminador (object sender, System.Windows.Forms.KeyPressEventArgs e) { //27 Corresponde a tecla ESC if (e.KeyChar == 27) { this.cboDeterminador.Text = determinador; }//Fim do IF }