Lesson 7 - Extend CStringArray and CString

Introduction

One of the reasons I left C and began to use C++ was CString and even more so CStringArray. These two classes are worth all the other aggravation when going OO. I don't claim that they are perfect. There are things missing in both of those classes and I would like to share this extension of CStringArray that I have made.

Finding an string in a CStringArray

One of the things that I think are missing in CStringArray is a Find method. I find myself wanting to get a specific string out of the array and I know part, or the whole, of it. Not the position in the array. So I added this method. It is very straight forward and uses CString::Find to find the string.

Example:

meStringArray arr;

// fill the array with strings using the normal Add()
arr.Add("This is a String");
arr.Add("The second string");
arr.Add("the 3:rd string");

// find the third string
int i=arr.Find("3:rd");

// i is now 2
CString sBuf;

sBuf=arr.GetAt(i);

// sBuf has now the value of "the 3:rd string"

Array of NULL terminating strings

Some SDK-functions and some classes still using an array of NULL terminating strings. e.g. CFileDialog uses this kind of array for the filters. GetProfileString("section",NULL,"",buf,sizeof(buf)); also uses it, and there are many more. So every time you need to use this class/function you have to go back to C and do a lot of loops. Well I finally got tired of it and extended CStringArray with two methods; AddBuf() and GetBuf(). The first will take an array of NULL terminating strings and add it to the StringArray, and the second will do the reverse

Example GetBuf:

CFileDialog dlg;
meStringArray filter;

// init filter
filter.Add("All files");
filter.Add("*.*");
filter.Add("Doc files");
filter.Add("*.doc");
filter.Add("Text files");
filter.Add("*.txt");

// Init file dialog
dlg.m_ofn.lpstrFilter=filter.GetBuf();
dlg.m_ofn.lpstrInitialDir=initDir;
dlg.m_ofn.Flags |= OFN_SHAREAWARE;
int rc=dlg.DoModal();
if(rc==IDOK)
{
m_filepath=dlg.GetPathName();
UpdateData(FALSE);
}
Example AddBuf:

meStringArray arr;
char buf[1024];

// Get all printer names
GetProfileString("devices",NULL,"",buf,sizeof(buf));

// add them to the array
arr.AddBuf(buf);

// Get the second printer name from the array
CString sPrintName = arr.GetAt(2);