Help translating from VB

Can someone help me translate this from VB to C++?

VB Code:

' Visual Basic version
Public Function LineTrim(Expression As String) As String
'Remove trailing CRs and LFs
    Dim sReturn As String
    Dim sCheck As String
    
    sReturn = Expression
    
    sCheck = Right(sReturn, 1)
 
    Do While (sCheck = Chr(10)) Or (sCheck = Chr(13))
        sReturn = Left(sReturn, Len(sReturn) - 1)
        sCheck = Right(sReturn, 1)
    Loop
    
    LineTrim = sReturn
    
End Function

and now the C++ version, which will be in a DLL for VB

Code:

---

LPCSTR LineTrim(LPCSTR *Expression)
{
    // I dont want to alter the original string,
    // so I need to declare this return value correct?
    LPCSTR ReturnVal;

    // How can I move the pointer to the end of the LPCSTR
    // without looping through it until '/0'

    // How can I check for the ascii value of the current char,
    // and shorten the string if it's CR or LF?

    LineTrim = ReturnVal;
}

---

Code:

---

LPCSTR LineTrim(LPCSTR line) {
        char *tmp =  new char[strlen(line)];

        strcpy(tmp,line);
        strrev(tmp);

        while(*tmp==char(10) || *tmp==char(13)){
                *tmp++;
        }
       
        return strrev(tmp);
}

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I think if you wanted to return a string to VB it had to be a BSTR, I'm not sure though

Ok thanks! I'll give it a try.

if I can remember vb(so long time didn't program on vb), but I think that it already have the function Trim() in vb...

Yeah it does, but it only trims spaces. I needed something that would trim carriage returns and line feeds as well..

While I'm here, is there a C++ function to get the Hexadecimal value of an expression?

Say I wanted the Hex value of "a", or of the number 72. Is there an existing method I can call?

You can use itoa, and give a radix of 16 :)

PS: How you return a string to VB is tricky because you can't deallocate the C++ memory within VB...

BSTR is the way to go, I believe.

yup its BSTR

Code:

---

BSTR LineTrim(BSTR line) {
        char *tmp =  new char[strlen((LPCSTR)line)];

        strcpy(tmp,(LPCSTR)line);
        strrev(tmp);

        while(*tmp==char(10) || *tmp==char(13)){
                *tmp++;
        }
       
        return (BSTR)strrev(tmp);
}

---

Quote:

---

Originally posted by brenaaro
Yeah it does, but it only trims spaces. I needed something that would trim carriage returns and line feeds as well..

While I'm here, is there a C++ function to get the Hexadecimal value of an expression?

Say I wanted the Hex value of "a", or of the number 72. Is there an existing method I can call?

---

http://www.vbforums.com/showthread.p...hreadid=199715

You are creating a memory leak -
Try (this is C)

Code:

---

unsigned int  in(char, char *);

char *rtrim(char *s){ // remove trailing blanks
    register char *buf;
    char *remove = " \n"; // change this to alter what gets whacked
    if(*s){
              for(buf=s;*buf;buf++);
              for(buf--;in(*buf,remove)&&(int(buf)>=(int)s; buf-- )
                  *buf=0x00;
    }
    return s;
}
unsigned int in(char ch,const char *test){
        unsigned int result=1;       
        register char *buf;
        for(buf=test;*buf,result;buf++) result=(ch==*buf);
        return result;
}

---

corrected version of naabels code:

Code:

---

BSTR LineTrim(BSTR line) {
        wchar_t *tmp =  new wchar_t[wcslen((LPCWSTR)line)];

        wcscpy(tmp,(LPCWSTR)line);
        wcsrev(tmp);

        while(*tmp==wchar_t(10) || *tmp==wchar_t(13)){
                tmp++;
        }
       
        BSTR ret = SysAllocString(wcsrev(tmp));
        delete [] tmp;
        return ret;
}

---

Avoids memory leaks and problem with incorrect usage of char.

Great work guys, thanks for all the code. I never would have figured it out by myself..well..maybe I would but it would have taken months! :eek:

Quote:

---

Originally posted by CornedBee
corrected version of naabels code:

Code:

---

BSTR LineTrim(BSTR line) {
        wchar_t *tmp =  new wchar_t[wcslen((LPCWSTR)line)];

        wcscpy(tmp,(LPCWSTR)line);
        wcsrev(tmp);

        while(*tmp==wchar_t(10) || *tmp==wchar_t(13)){
                *tmp++;
        }
       
        BSTR ret = SysAllocString(wcsrev(tmp));
        delete [] tmp;
        return ret;
}

---

Avoids memory leaks and problem with incorrect usage of char.

---

ah coolio..wheres the memory leaks? i wanna get this right :)

BSTR is more than just a cast.
a) It's UNICODE, so you can't simply copy it to a ANSI string (that's why I used wchar_t).
b) It's counted, so you should use SysAllocString, which creates a completly valid BSTR for you.
c) You still don't free the memory allocated by new. And if you don't, no one else will (surely not VB).
d) *tmp++; don't dereference here.

Code:

---

BSTR LineTrim(BSTR line) {
        char *tmp =  new char[strlen((LPCSTR)line)];

        strcpy(tmp,(LPCSTR)line);
        strrev(tmp);

        while(*tmp==char(10) || *tmp==char(13)){
                *tmp++;
        }
       
        return (BSTR)strrev(tmp);
}

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