文字列のコピー

C Delphi

明解Ｃ言語 入門編 > 11. 文字列とポインタ >

文字列のコピー

C



#include <stdio.h>

#include <string.h>
char* str_cpy(char* d, const char* s)

{

    char* t = d;
    while (*d++ = *s++)

        ;
    return t;

}
int main(int argc, char* argv[])

{

    int i;

    char* st1 = "12345";

    char* st2 = "ABC";
    printf("st1 = %s\n", st1);

    printf("st2 = %s\n", st2);

    puts("");
    str_cpy(st1, st2);

    printf("st1 = ");

    for (i = 0; i < 5; i++)

        if (st1[i] == '\0')

            putchar(' ');

        else

            putchar(st1[i]);

    putchar('\n');

    printf("st2 = %s\n", st2);

    puts("");
    st1 = "12345";

    strcpy(st1, st2);

    printf("st1 = ");

    for (i = 0; i < 5; i++)

        if (st1[i] == '\0')

            putchar(' ');

        else

            putchar(st1[i]);

    putchar('\n');

    printf("st2 = %s\n", st2);

    puts("");
    return 0;

}

実行結果



R:\>lesson085\project1.exe

st1 = 12345

st2 = ABC
st1 = ABC 5

st2 = ABC
st1 = ABC 5

st2 = ABC

Delphi



program Project1;
{$APPTYPE CONSOLE}
uses

    SysUtils;
function str_cpy(d:PChar; s:PChar):PChar;

begin

    result := d;
    repeat

        d^ := s^;

        Inc(s);

        Inc(d);

    until (s^ = #0);
    d^ := s^; { \0 も COPY }

end;
procedure main();

const

    st1: String                = '12345';

    st2: String                = 'ABC';
    pt1: array[0..255] of Char = '12345';

    pt2: array[0..255] of Char = 'ABC';

var

    i: Integer;

begin

    Writeln(Format('st1 = %s', [st1]));

    Writeln(Format('st2 = %s', [st2]));

    Writeln('');
    st1 := st2;

    Writeln(Format('st1 = %s', [st1]));

    Writeln(Format('st2 = %s', [st2]));

    Writeln('');



    Writeln(Format('pt1 = %s', [pt1]));

    Writeln(Format('pt2 = %s', [pt2]));

    Writeln('');
    str_cpy(pt1, pt2);

    write('pt1 = ');

    for i := 0 to 4 do

        if pt1[i] = #0 then

            write(' ')

        else

            write(pt1[i]);

    Writeln('');

    Writeln(Format('pt2 = %s', [pt2]));

    Writeln('');



    pt1 := '12345';

    Writeln(Format('pt1 = %s', [pt1]));

    Writeln(Format('pt2 = %s', [pt2]));

    Writeln('');
    StrCopy(pt1, pt2);

    write('pt1 = ');

    for i := 0 to 4 do

        if pt1[i] = #0 then

            write(' ')

        else

            write(pt1[i]);

    Writeln('');

    Writeln(Format('pt2 = %s', [pt2]));

    Writeln('');

end;
begin

    main;

end.

実行結果



S:\>lesson085\project1.exe

st1 = 12345

st2 = ABC
st1 = ABC

st2 = ABC
pt1 = 12345

pt2 = ABC
pt1 = ABC 5

pt2 = ABC
pt1 = 12345

pt2 = ABC
pt1 = ABC 5

pt2 = ABC