i cannot for the life of me figure out how to create the following an array of static arrays. below is a picture of what i mean. I want to be able to advanced my pointer 1 byte and hit another string. Is the following even possible?
http://craz.net/Snapper/live/view/?s=r6t
Array of Arrays?
I think what you're looking for is char[][256]; I wrote a post about something similar a while ago... It might be what you're looking for.
What language are you using? Do you want to be able to dynamically add and remove rows from the outer array?
Author
I need to dynamically add rows and im using C++.
FastCall22 - I will look at your post and see if it's what im looking for
FastCall22 - I will look at your post and see if it's what im looking for
Have you tried std::vector<std::string>?
If you really need the inner arrays to have an upper limit of 255 characters for some reason, I recommend writing a type for that and putting this type in a vector. At its simplest this could be wrapping a raw array in a struct. A better approach might internalise the details such as ensuring correct handling of the ever troublesome NUL character (assuming you want to use C-style strings).
If you really need the inner arrays to have an upper limit of 255 characters for some reason, I recommend writing a type for that and putting this type in a vector. At its simplest this could be wrapping a raw array in a struct. A better approach might internalise the details such as ensuring correct handling of the ever troublesome NUL character (assuming you want to use C-style strings).
struct short_string
{
public:
// std::string-like interface
private:
char data[256];
};
// Later
std::vector<short_string> v;
You may use std::array (fixed-size array) in conjunction with std::vector (dynamic array): http://ideone.com/W2RGh
The standard guarantees that both std::array and std::vector are contiguous -- and, hence, support pointer walk-through that you desire:
http://herbsutter.co...-be-contiguous/
If you do that, please be wary of the need to adopt a convention regarding the gaps -- as recommended above, NUL terminator might be a good idea.
However, if you want you can also access each individual word with the usual indexing (MyWords[0], MyWords[1], MyWords[2], ...) which I believe might be easier on the readers of your code :-)
The standard guarantees that both std::array and std::vector are contiguous -- and, hence, support pointer walk-through that you desire:
http://herbsutter.co...-be-contiguous/
If you do that, please be wary of the need to adopt a convention regarding the gaps -- as recommended above, NUL terminator might be a good idea.
However, if you want you can also access each individual word with the usual indexing (MyWords[0], MyWords[1], MyWords[2], ...) which I believe might be easier on the readers of your code :-)
Another common thing done for 2D arrays is just use a 1D array and multiply.
The benefit of a 1D array is that, unlike a std::vector< std::vector<type> >, you are sure every row is the same width, and that iteration over the vector is very easy: just iterate over it like a 1D array, but when wanting to access a 2D cell, then index as shown above.
//Creation:
std::vector<MyType> myArray;
myArray.resize(HEIGHT * WIDTH);
//Accessing by x and y:
int index = (Y * WIDTH) + X;
myArray[index] = ...;
The benefit of a 1D array is that, unlike a std::vector< std::vector<type> >, you are sure every row is the same width, and that iteration over the vector is very easy: just iterate over it like a 1D array, but when wanting to access a 2D cell, then index as shown above.
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