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Something very wierd and confusing

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Well ill post abit of the code below but basical this function checks to see if two LPSTR strings are the same and if so does whats int he if statment but it dose not do that at all even thought the message boxs output says there the same so just alittle confused as to why this is not working im using VC++ express void LINKEDLIST::DeleteListNode(LPSTR WindowID) { ListNode *ListPtr, *ListPtr2; ListPtr = ListHeader; if(ListPtr->WindowID == WindowID) { ListHeader = ListPtr->Next; delete ListPtr; } ListPtr2 = ListHeader; while(ListPtr != NULL) { MessageBox(NULL,WindowID,ListPtr->WindowID,MB_OK); if(WindowID == ListPtr->WindowID) { ListPtr2->Next = ListPtr->Next; delete ListPtr; MessageBox(NULL,"Item Removed From List",NULL,MB_OK); return; } ListPtr2 = ListPtr; ListPtr = ListPtr->Next; } MessageBox(NULL,"Nothing removed from list",NULL,MB_OK); return; } so yeah any thoughts would be nice -.^

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When comparing two LPSTRs, you are comparing the pointers, not what they are pointing at. (LPSTR is a typedef for "long pointer to string"). So:

if ( listPtr->WindowID == WindowID )

...will return true if and only if the pointers are the same. That need not be the case - consider:

int a = 1;
int b = 1;
int* p1 = &a;
int* p2 = &b;
if ( p1 == p2 ) { /* will never get here */ }
if ( *p1 == *p2 ) { /* will get here */ }

Sounds like you want to check if the strings are the same, something like as follows:

if ( strcmp( listPtr->WindowID, WindowID ) == 0 )

... where strcmp is a function that compares strings, returning how different they are (so 0 is identical).

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LOL oh duh ..... way to make myself seem stupid i had a sneaky suspicion about that.

Well thanks for your time!

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