Converting strings to chars

This is a discussion on Converting strings to chars within the C++ Programming forums, part of the General Programming Boards category; I want to convert few strings, ex: Code: string1 = "abc"; string2 = "123"; to array of characters, ex: char1[0] ...

  1. #1
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    Converting strings to chars

    I want to convert few strings, ex:
    Code:
    string1 = "abc";
    string2 = "123";
    to array of characters, ex:
    char1[0] = 'a';
    char1[1] = 'b';
    char1[2] = 'c';

    char2[0] = '1';
    char2[1] = '2';
    char2[2] = '3';
    How can I do this?

  2. #2
    and the hat of wrongness Salem's Avatar
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    char foo[10];
    strcpy( foo, string.c_str() );
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  3. #3
    Malum in se abachler's Avatar
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    Code:
    BYTE Foo[10];
    DWORD Index = 0;
    
    
    while((string1[Index] !=0) && (Index < 10)){
         CopyMemory(&Foo[Index] , &string1[Index] , 1);
         Index++;
         }
    This code avoids overruns in the case where the string isnt properly termianted with a NULL
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  4. #4
    Frequently Quite Prolix dwks's Avatar
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    No, actually, it doesn't. If the string is 3 characters long, but doesn't have a NULL terminator, you just keep copying. And your code acts like strncpy(): if the string is longer than 10 characters, you don't add a terminator to it.

    And to top it off, that code is Windows-only. Why do it unportably if you can do it portably? At the very least, mention that it is Windows-specific, especially when the OP said nothing about Windows programming.
    dwk

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  5. #5
    Cat without Hat CornedBee's Avatar
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    And why use a range copy call when the = has the same semantics? For PODs, this:

    CopyMemory(&Foo[Index] , &string1[Index] , 1);

    is the same as

    Foo[Index] = string1[Index];

    except slower, more complicated, less readable and more error-prone.

    To get a mutable C-style array of characters, I'd use this:
    Code:
    std::vector<char> v(string1.begin(), string1.end());
    FunctionThatWantsCharPtr(&v[0], v.size());
    All the buzzt!
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