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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'


That's not what i want. 
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