Print a String Variable

Programming Support VEXcode Pro V5 Text Tech Support
1

In VEXcode, how do I print a variable in string form? I am drawing a map of the field on the screen for auton selection purposes. I need to define a string variable in the function declaration, use it to print to the brain screen, and define the variable where I call my function.
I have a function like this:

void drawMap (std::sting desc){
    Brain.Screen.PrintAt(240, 40, [print the variable in here somewhere]);

}


int main(){
    drawMap("I am writing a description here. This is what should be printed on the brain");
}
2 
Brain.Screen.PrintAt(240, 40, "someString will be printed here: %s", someString);

Take a look at how to use printf() for more context.

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4

I still get the error

5

It will be difficult to help you further without seeing the rest of your code.

6

You are trying to pass an std::string which is a class. It can only accept char * (a character array). std::string does have a function to get it as a char array: .c_str(). So your code should look like this…

Brain.Screen.printAt(240, 40, "Description: %s", desc.c_str());
4 Likes
7

This didn’t fix it.

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8

In cpp there is the idea of function overloading, where two function can have the same name, but different variables. The Screen class has two functions…

printAt( int32_t x, int32_t y, const char *format, ... );
printAt( int32_t x, int32_t y, bool bOpaque, const char *format, ... );

The problem is that it is unable to decide which function you are trying to use, since it can convert the char * to a bool and then the second char *, from the string, can work as the format parameter.

To fix this just add a bool to tell it you want to use the second function…

Brain.Screen.printAt(240, 40, false, "Description: %s", desc.c_str());
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