[C#] Keyword Coloring

[Hell-Lord]

I need to color some keywords in C# and was wondering if adding the keyword to a HashTable would be the best way?

The keywords are stored like so...

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string[] keywords = {"word","word",
                   "word","something"
                   "so on","more"};

Any ideas that could be more efficient that using a HashTable?

Edit:
Hmm might it be easier to store all the keywords in a text file, then put all the words in an array?

[MyndFyre]

Doing it for a web app or winforms?

IMO, keyword colorizing is one of my least favorite activities.

[Hell-Lord]

I'm doing it in a winform.

[brew]

Not C#, but this might help:

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#define NUM_KEYWORDS (7)
const unsigned int keywordlens[] = {2, 3, 5, 5, 4, 8, 6};
const char *keywords[] = {
"if",
"for",
"while",
"var32",
"void",
"function",
"return"
};

LRESULT CALLBACK RTBProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam) {
if (iMsg == WM_CHAR) {
char asdf[128];
CHARRANGE CharRange;
TEXTRANGE textrange;
for (int i = 0; i != NUM_KEYWORDS; i++) {
SendMessage(hwnd, EM_EXGETSEL, 0, (LPARAM)&CharRange);
ZeroMemory(asdf, sizeof(asdf));
textrange.chrg.cpMin = CharRange.cpMin - keywordlens[i];
textrange.chrg.cpMax = CharRange.cpMin;
textrange.lpstrText = asdf;
SendMessage(hwnd, EM_GETTEXTRANGE, 0, (LPARAM)&textrange);
if (!strcmp(asdf, keywords[i])) {
CharRange.cpMax = CharRange.cpMin;
CharRange.cpMin -= keywordlens[i];
SendMessage(hwnd, EM_EXSETSEL, 0, (LPARAM)&CharRange);
cfFormat.crTextColor = 0x00FF0000;
SendMessage(hWnd_rtb, EM_SETCHARFORMAT, SCF_SELECTION, (LPARAM)&cfFormat);
CharRange.cpMin += keywordlens[i];
CharRange.cpMax = CharRange.cpMin;
SendMessage(hwnd, EM_EXSETSEL, 0, (LPARAM)&CharRange);
cfFormat.crTextColor = 0x00FFFFFF;
SendMessage(hWnd_rtb, EM_SETCHARFORMAT, SCF_SELECTION, (LPARAM)&cfFormat);
goto _end;
}
}
} else if ((iMsg == WM_LBUTTONUP) || (iMsg == WM_RBUTTONUP)) {
SendMessage(hWnd_rtb, EM_EXGETSEL, 0, (LPARAM)&CurrentLineRange);
}
_end:
UpdateStatusBar();
return CallWindowProc(oldRTBProc, hwnd, iMsg, wParam, lParam);
}

the keyword len array is really just there to speed it up so i don't have to call strlen on static strings (my method is quite slow, i needed to optimize it)

[Banana fanna fo fanna]

In general, a hash table is the best data structure for this. Go for it.

[MyndFyre]

I'm curious as to why a hash table is the best?  Why not an array list, a linked list, anything else that isn't an associative/dictionary thing?

[Hell-Lord]

I'm thinking of going with the Hash Table because i am only really dealing with one column of data.

[MyndFyre]

That's pretty much a reason to not go with a hash table.

Go with a plain old array.  If you can't deal with that, go with an ArrayList/List<T>.  If you REALLY want performance for multiple additions without reallocation hits, use a LinkedList<T>.  If you want order, use a List<T> and provide a Comparison<T> delegate.  But for god's sake, don't use a Hashtable to store nonkeyed data.

[Hell-Lord]

 I was under the impression that with multiple columns of data an array would be best or a data table. But for something so simple a Hash Table would be best suited.

If you REALLY want performance for multiple additions without reallocation hits, use a LinkedList<T>.

Never thought of that, ill test it out now.

[MyndFyre]

List<T> is more memory-performant than a LinkedList<T> as long as it doesn't need to be resized.  It also performs about as quickly as an array, roughly O(1).  LinkedList<T> is O(n) for searches, but just about O(1) for extensions (while List<T> is O(n) for extensions).

For single columns of data, arrays, array lists, and linked lists are always the best.

[Banana fanna fo fanna]

doesn't he need to store what color each keyword is going to be? i feel like a hashtable would be the perfect solution seeing as it's designed to map keys (keywords) to values (colors)...

[MyndFyre]

doesn't he need to store what color each keyword is going to be? i feel like a hashtable would be the perfect solution seeing as it's designed to map keys (keywords) to values (colors)...

If that were the case tben yes, a hashtable (actually, a Dictionary<TKey, TValue>) would be the best way to do it.  But he said:

i am only really dealing with one column of data.

...which means the data should be nonassociative.

[Banana fanna fo fanna]

doesn't he need to store what color each keyword is going to be? i feel like a hashtable would be the perfect solution seeing as it's designed to map keys (keywords) to values (colors)...

If that were the case tben yes, a hashtable (actually, a Dictionary<TKey, TValue>) would be the best way to do it.  But he said:

i am only really dealing with one column of data.

...which means the data should be nonassociative.

Missed that...my bad

[Smarter]

Yeah, I was going to suggest a Dictionary:

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Dictionary<string, Color> keyWords = new Dictionary<string, Color>();
keyWords.Add("word", Color.Red);


Along those lines?

[Hell-Lord]

There stored in a string array though.