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D - from char[] to byte

reply Manfred Hansen <manfred toppoint.de> writes:
Hi,

how can i cast from char[] to byte?

import outbuffer;

int main () {
        //byte by = 0x4d;
        byte  by;
        OutBuffer buf = new OutBuffer();
        char [] del=' ',hex_string ='0x4d 0x42';
        char [][] str;

        str = split(hex_string,del);
        printf("%.*s\n",str[0]);
        by = cast(byte) str[0];
        buf.write(cast(byte)by); // Here is the problem
        printf("buf = '%.*s'\n", buf.toString());
        return 0;
}

By the way, the linux port from dmd works nice.


Regards Manfred
May 18 2003
parent reply Ilya Minkov <midiclub 8ung.at> writes:
Manfred Hansen wrote:
 Hi,
 
 how can i cast from char[] to byte?

I don't understand what kind of conversion result you expect.
 import outbuffer;
 
 int main () {
         //byte by = 0x4d;
         byte  by;
         OutBuffer buf = new OutBuffer();
         char [] del=' ',hex_string ='0x4d 0x42';
         char [][] str;

So "str" is an array of strings.
 
         str = split(hex_string,del);
         printf("%.*s\n",str[0]);
         by = cast(byte) str[0];

you're converting an *array* (a string) into a *value* - which makes no sense. Have you meant: by = cast(byte) (str[0][0]);
         buf.write(cast(byte)by); // Here is the problem

why here? "by" is a byte, casting it to byte is redundant.
         printf("buf = '%.*s'\n", buf.toString());
         return 0;
 }

Thus modified proggie gives following output: 0x4d buf = '0' -i.
May 18 2003
parent reply Manfred Hansen <manfred toppoint.de> writes:
Ilya Minkov wrote:

 Manfred Hansen wrote:
 Hi,
 
 how can i cast from char[] to byte?

I don't understand what kind of conversion result you expect.

I want the output 'M' . 4d is the ASCII code for M. In my real programm i will sent hex number's to the socket for communication to the mysql server (linux), but i believe this is a long way.
 
 import outbuffer;
 
 int main () {
         //byte by = 0x4d;
         byte  by;
         OutBuffer buf = new OutBuffer();
         char [] del=' ',hex_string ='0x4d 0x42';
         char [][] str;

So "str" is an array of strings.
 
         str = split(hex_string,del);
         printf("%.*s\n",str[0]);
         by = cast(byte) str[0];

you're converting an *array* (a string) into a *value* - which makes no sense. Have you meant: by = cast(byte) (str[0][0]);
         buf.write(cast(byte)by); // Here is the problem

why here? "by" is a byte, casting it to byte is redundant.

Oh, yes this was wrong from me. I mean'd this line " by = cast(byte) str[0];"
 
         printf("buf = '%.*s'\n", buf.toString());
         return 0;
 }

Thus modified proggie gives following output: 0x4d buf = '0'

I will get buf = 'M' .
 
 -i.

Regards Manfred
May 18 2003
parent Ilya Minkov <midiclub 8ung.at> writes:
Manfred Hansen wrote:
 I want the output 'M' .
 4d is the ASCII code for M.
 In my real programm i will sent hex number's to the socket 
 for communication to the mysql server (linux), but i believe this 
 is a long way.

Hmm... hex numbers? Well, as you wish. I know nothing about MySQL.
 Oh, yes this was wrong from me. 
 I mean'd this line " by = cast(byte) str[0];"  

str is an *array* of *strings*. It is like you have a sheet of lined paper, on which you must first select a line, then a column. That is, you want to take one character like: by = str[line][column]; //add a cast if it complains str[x] would give you the whole line of charcters. Also think whether a string would be more appropriate ("char [] str;") - i'm still unclear about what you want and how you intend it to work, bit the name "str" suggests it being a string, not an array of strings. Then, if you want to print a byte as a character, why don't you cast it into a character? Consider: "buf.write" resolves to different functions depending on a formal data type. -i.
May 18 2003