Re: Simple code in Pascal -> C

Chris Brooks Wed, 04 May 2005 02:13:24 -0700

Andre,

This line...

StrCopy( FieldText,  RecordPtr[*Offset]);

Should read

StrCopy( FieldText,  RecordPtr+(*Offset));

The problem you have there is because using [] means an index into an array...

for example

char test[10];

   test[3] = 'A';

this code makes the fourth character (indexes start at zero) a capital A

if you had

char *test[10];

your declaring 10 pointers to strings, not 10 characters in a string.

back to your code:-

StrCopy( FieldText,  RecordPtr[*Offset]);<=================

this says copy from the RecordPtr array to the FieldText

and what you want is cpy fromthe record pointer PLUS an offset to the FieldText....

clear as mud :-)

You really need to read a book on C,or one of the many good tutorials available online.

Chris.


Andre Augusto wrote:

Thanks for your help!
One more thing... can you tell me if this function is correct?

void SetFieldValue( FieldPtr field, UInt16 fieldLen, UInt16 *Offset)
///Problema em ler o valor Offset
{
 MemHandle FieldTextHandle;
 const char*  FieldText;
 DBRecordPtr RecordPtr;

 FieldTextHandle = FldGetTextHandle(field);
 // Clear any existing text first
 FldSetTextHandle(field, NULL);


 if (FieldTextHandle == NULL)
 {
   FieldTextHandle = MemHandleNew(fieldLen);
 }
 else
 {
   MemHandleResize(FieldTextHandle, fieldLen);
 }

 FieldText = (const char*) MemHandleLock(FieldTextHandle);
 RecordPtr = (DBRecordPtr) MemHandleLock(CurrRecHandle);

 StrCopy( FieldText,  RecordPtr[*Offset]);<=================
//  *Offset += StrLen(RecordPtr[*Offset]) + 1;

 MemHandleUnlock(CurrRecHandle);
 MemHandleUnlock(FieldTextHandle);
 FldSetTextHandle(field, FieldTextHandle);
}

In PASCAL it's like this:
procedure SetFieldValue(Field : FieldPtr;FieldLen : UInt16;var Offset :
UInt16);
 var
   FieldTextHandle : MemHandle;
   FieldText       : PChar;
   RecordPtr       : PChar;
begin
 FieldTextHandle := FldGetTextHandle(Field);
 // Clear any existing text first
 FldSetTextHandle(Field,nil);

 if FieldTextHandle = nil then begin
   FieldTextHandle := MemHandleNew(FieldLen);
 end else begin
   MemHandleResize(FieldTextHandle,FieldLen);
 end;

 FieldText := MemHandleLock(FieldTextHandle);
 RecordPtr := MemHandleLock(CurrRecHandle);

 StrCopy(FieldText,@RecordPtr[Offset]);
 Offset := Offset + StrLen(@RecordPtr[Offset]) + 1;

 MemHandleUnlock(CurrRecHandle);
 MemHandleUnlock(FieldTextHandle);

 FldSetTextHandle(Field,FieldTextHandle);
end;

The OffSet value that is passed to the function is "var OffSet". So how can i pass it in C language? like &offset? Or *offset? In the line that I put an arrow I have an error saying: "function call 'StrCopy({lval} const char *, {lval} DBRecord *)' does not match 'StrCopy(char *, const char*)' "


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Re: Simple code in Pascal -> C

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