Allegro - trying to read text from a file and print on screen
Author
Hello all!
I need to read text from a normal Windows .txt file and print it on the screen in graphics mode using Allegro, but am stuck.
I have been able to load text into a string object:
std::ifstream file ("example.txt");
string str;
getline(file, str);
That works just fine. I can also print a string to the screen, in a separate function:
char* str[30];
str[1]=input;
textprintf(m_Buffer, font, 0, i*10, WHITE, "Test: %s", str[1] );
This second function has 30 messages stored in an array of pointers to characters, or something.
You can see the problem, can't you. I seem to be using two different types of string. Firstly I'm using C++ string objects. Then I'm using something else (the old C style strings? I'm not sure exactlly). The two seem incompatible.
Firstly, does anyone know if I can print new C++ strings to the screen in Allegro using textprintf()?
If that cannot be done, do I need to convert the string or should I be loading it in from the text file in a different way?
*headscratch* *headscratch*
Hmm.
Author
I don't really understand. Does it point to the C++ string object? And therefore can be used in the Allegro textprintf()?
If you have a string string and want to convert it to a null-terminated c-style string, just do this...
and thats all it takes c_str() returns a null terminated char array string.
[edit] i was beat to it by Roboguy
string name("Michael");char name[8] = name.c_str();and thats all it takes c_str() returns a null terminated char array string.
[edit] i was beat to it by Roboguy
Author
OK, I have tried it like this...
string str="yipee!";
char name[6] = (str.c_str());
But I get a invalid initializer error. Any ideas?
string str="yipee!";
char name[6] = (str.c_str());
But I get a invalid initializer error. Any ideas?
Author
What does that do? Create a new c++ style string object, then copy it into a character?
It compiles but it doesn't seem to let me do anything with it. I want to pass it to another function, my function that draws char arrays on the screen. I've tried passing it like this:
m_Test.Input(5, name);
m_Test.Input(5, *name);
It compiles but it doesn't seem to let me do anything with it. I want to pass it to another function, my function that draws char arrays on the screen. I've tried passing it like this:
m_Test.Input(5, name);
m_Test.Input(5, *name);
What do you mean? Does it give a compiler error? Does it crash? Is there a runtime error? Does the m_Test.Input take a const char* or a std::string?
Author
m_Test.Input takes a pointer to a string of chars, if my terminology is correct:
void Test::Input(int line, char* input)
{
m_Input[line]=input;
}
If I try to do this:
std::string string = "yipee";
const char* name = string.c_str();
m_Test.Input(1, name);
I get 'invalid converstion from 'const char' to 'char'.
Hmm...
void Test::Input(int line, char* input)
{
m_Input[line]=input;
}
If I try to do this:
std::string string = "yipee";
const char* name = string.c_str();
m_Test.Input(1, name);
I get 'invalid converstion from 'const char' to 'char'.
Hmm...
Author
Have also tried a more direct approach...
m_Test.Input(1, *string.c_str());
...and get the same.
Am thinking maybe it is better to read the file in using chars instead, it just seems sort of weird to read it in using C++ style string objects then have to convert it to chars before I print it.
m_Test.Input(1, *string.c_str());
...and get the same.
Am thinking maybe it is better to read the file in using chars instead, it just seems sort of weird to read it in using C++ style string objects then have to convert it to chars before I print it.
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