problems with strings

Hey guys, I was wondering if any of you could help me with some stuff which may seem obvious to you but I'm a beginner.

I'm making a calculator and have reached the part where I am making the buttons change the string on the calculator's "screen".

The way I am doing this is by getting the current line of numbers as a string and then converting the number pressed into a string and then adding the two strings together to form the new calculator display, I then want to display that string.

After reading some books and looking online I thought the best way of doing this would be to use string streaming, so I have made the following:

Code:

 if(ButtonType == 1) // Numerical buttons processed here
                        {
                                CurrentInputString = "";
                                CurrentInput = 0;
                                CurrentInput = ButtonNumber;
                                InputOutputStream > CurrentInputString;
                                InputOutputStream.str("");
                                InputOutputStream.clear();

                                InputOutputStream > TotalInputString;
                                InputOutputStream.str("");
                                InputOutputStream.clear();

                                InputOutputStream  TotalInput;
                                InputOutputStream > TotalInputString;
                                InputOutputStream.str("");
                                InputOutputStream.clear();
                                this->InputLabel->Text = Convert::ToString(TotalInput);

                        }

I had problems setting the text as "TotalInputString" and got these compiler messages:

So my question is - how do I do this? All I want is for the string to allow me to place as many numbers as I need on the display. How do I change the text in such a way?


This was done on Visual C++, sorry if that's a problem.


Thanks in advance to anyone who helps.