Question about chars

JR · **Posted:** Sat Nov 22, 2008 1:10 pm

Hey i'm making a small one line text editor.
in my code i have insert mode and overstrike mode.

so lets say i have some text: abcdefX Y

String length is 20 chars for example

how do i make it add characters to it after the X(end of text, but not the length of the whole string, just used as example)
it works perfectly when i try to edit the text itself or enter the characters on the X or before, but when i move to Y for example it doesn't display the characters i enter.

if you need to see the code i'll post it up.

md · **Posted:** Sat Nov 22, 2008 2:47 pm

I am unsure of your question. Are you wondering how to insert text into the character array? Or is this a UI issue?

And code would be nice.

JR · **Posted:** Sat Nov 22, 2008 4:36 pm

this is not UI, just a simple console 1 line editor. lets say the Array is 50 chars, but only 30 are used i can insert chars into the 31st position, but if i move over to the 32nd -49th i cant insert anything.

here is my edit function where all the text is inserted etc.

se - the string
slen - string length
flen is the field length, i use a field to where i write the text.
*start is where the cursor starts in the field
*offset is the location of the text corresponding to the field
ctype - is for later use, not implemented yet.

code:

int dt_edit(char *se, int slen, int row, int col, int flen,
int *start, int *offset, int *insert, int ctype){
int done = 0;
int ch = 0;
int OldStart = *start;
char Oldstring[slen];
int i =0;
int ii;
int len = 0;
strcpy(Oldstring,se);

while(!done){
dt_draw(se + *offset,row, col, flen);
dt_cursor(row, col + *start);
ch = dt_getkey();
switch(ch){
   case ESC:
   *start = OldStart;
   strcpy(se,Oldstring);
   done = 1;
   break;
   case RIGHT:
   if(*start != flen)
   (*start)++;

   else if(*start+*offset < slen)
   (*offset)++;

   break;

   case DEL:
   for(i=*start+*offset;se[i];i++)
   se[i]=se[i+1];
   break;

   case LEFT:
   if(*start > 0)
   (*start)--;
   else if(*offset > 0)
   (*offset)--;
   break;
   case BS:
   len = strlen(se) - 1;
   if(*offset+*start != *offset)
   {
   for(i=*start+*offset;se[i]-1;i++)
   {
   se[i-1] = se[i];

   }
   *start = *start - 1;
   }
   else if(*offset+*start == *offset && strlen(se) !=0 && *offset >0)
   {

   (*offset)--;
   for(i=*offset+1;se[i];i++)
   {
   se[i-1] = se[i];
   }

   se[len] = 0;

   if(*offset + *start !=0 && *offset >2){
   (*offset) -= 2;
   (*start) +=2;
   }
   else if(*offset != 0)
   { (*offset)--;
   (*start)++;}
   }

   break;
   case HOME:
   *offset = *start = 0;
   break;
   case INS:
   *insert = !(*insert);
   /*if(*insert == 0){
   *insert = 1;
   }
   else{
   *insert = 0;
   }*/
   break;

   case ENTER:
   case TAB:
   case UP:
   case DOWN:
   case PGUP:
   case PGDN:
   case F1:
   case F2:
   case F3:
   case F4:
   case F5:
   case F6:
   case F7:
   case F8:
   case F9:
   case F10:
   done = 1;
   break;

   default:

   len = strlen(se) +1;

   if (*start == flen && strlen(se) != slen && (*start + *offset) < slen)
   {
   (*start)--;

   (*offset)++;
   }

   if (ch>=32 && ch<=126){
   if (*insert){
   if(strlen(se) < slen && strlen(se) !=0)
   {

   if (*start + *offset < slen)
   {
   for(ii=strlen(se)-1;ii>=*start+*offset;ii--)
   {
   se[ii+1] = se[ii];

   }
   se[*start+*offset]=ch;
   (*start)++;
   se[len]=0;

   }

   }

   }

   else
   {
   if(*start == flen && strlen(se)!= slen)
   {
   (*start)--;
   (*offset)++;
   }
   if(strlen(se) < slen)
   {

   if(se[*offset+*start] == 0){
   se[*offset+*start+1] = 0;
   }
   se[*offset+*start] = ch;
   (*start)++;
   }
   }
   }
   break;
}
}
return ch;
}

md · **Posted:** Sun Nov 23, 2008 2:33 pm

I'm still not sure I understand the question, if you are asking how to insert characters into a char* based string it's pretty simple

code:

WHILE characters to insert AND space in string DO
FOR i = position to insert character to end of string DO
string[i+1] = string[i]
string[position to insert character] = character to insert

Then you either increase the position that you are inserting a character in for every character, or do it the easy way and reverse the string you are inserting.

DemonWasp · **Posted:** Tue Nov 25, 2008 11:43 pm

md, I think you mean:

code:

WHILE characters to insert AND space in string DO
FOR i = (end of string) to (position to insert character) BACKWARDS DO
string[i+1] = string[i]
string[position to insert character] = character to insert

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