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When you declare a nested class as a friend of its containing class, place the friend declaration after the declaration of the nested class, not before: class A // containing
Question: I’m trying to install a search facility on a database program I have written using VB6 and an Access database. I’ve opened by inserting a data control onto my
Question: I’d like to know how can I make a return of a function’s local variable (for example, a reference to it) not using pointers technique? Answer: You have tow
Question: I am getting a compile error ‘huge’ obsolete keyword. I am converting a process from Visual C++ 2.0 to 6.0. What keyword could I use in place of ‘huge’?
Question: How can I dynamically build a procedure call string and then get it to execute? Ex. Dim action as String action = “proc(param1,param2)” call action I know this does
Question: In MFC, what does the following declaration do? CPen::operator HPEN() const; My understanding of the operator keyword is that you cannot use it to create a new operator; however,
This control lets you have two applications that communicate with each other. Just select the target application by its handle or partial/whole caption, set the string or the Long data
When you use JIT activation in particular there is a special situation that you have to be prepared for. While discussing that issue, I will also show a trap when
When working with a forward-only, read-only Recordset – that is, the default ADO Recordset – the RecordCount property always returns -1. (This can also happen with other types of server-side
Suppose you have two tables named Table1 and Table2 with one or more fields named the same way. Now, consider this query: rs.Open “SELECT * FROM table1 INNER JOIN table2
The syntax for opening a password-protected Jet database might not be obvious. In fact, assigning the password to the Password property in the ConnectionString raises the following error: Run-time Error:
If you try to use a DataList and some labels or text boxes linked to an ADO Data control, and you click on some items in the list, you’ll notice
A file DSN is nothing but a text file that contains all the parameters for an ODBC connection. To prove this, just go to the default directory that holds all
o briefly recap the situation I described in “All the Changes, All the Time: Part I“, my assignment was to capture all the changes being made in one database and,
Here is a little tip to check if any of your .class files are corrupted or if they are not .class files generated from a .java file. There
You can connect a MS-Access database to SQL Server as a linked server, and query Access tables in SQL Server’s Query Analyzer. This can help in porting data from Access
LIKE is probably the VB operator is most underutilized if compared to its potential. The most immediate use for this operator is to check that a string begins or ends
Constructor is a special kind of method which gets called automatically whenever the object is created. One class can have zero, 1 or more then 1constructors. Basically, you can overload
Question: I have several forms in different pages which are linked using a tab approach. I would like to pop-up a confirmation window if someone is moving from one tab
Question: Why is the following code not working? Javascripts January Februrary March 1 2 3 4 5 2000 2001 passdate1: January Februrary March 1 2 3 4 5 2000 2001
Question: How can I make different CSS styles to be loaded depending on the platform a user has (Mac or PC)? Answer: The simplest way to do this is to
It can be very useful to have a central public function for manipulating themouse pointer in a Visual Basic application. This function can help youorganize how the hourglass is shown
Always be careful when checking adoRS.Fields(i).Name, the stringfor this property is case sensitive. If in a database there’s a field named BANK_BALANCE_AMT,RS.Fields(i).Name will not recognize “bank_balance_amt”: In such a case
The standard locale framework was added to ANSI/ISO C++ in 1994. In essence, it consists of template classes called “locales”, which use facets. A facet represents a certain cultural convention
Consider the following class: class A{public: A(int size);private: int size;}; You can initialize the member size in at least three forms: A::A (int size) : size (size) { } //
Although you can allocate multidimensional arrays manually, as in: int (*ppi) [5]=new int[4][5]; // parentheses required // fill arrayppi[0][0] = 65;ppi[0][1] = 66;ppi[0][2] = 67;//
Remember that functions defined inside the class definition are implicitly inline. Therefore, the inline keyword is redundant in the definition of the member function of the following class: class Employee{public:
To copy the contents of one file into another, use the fstream classes. First, open the source file using an ifstream object, then create a target file using ofstream, and
Imagine you have an enormous object serialized on disk that you are using in memory, or that object is loaded in memory. You want to allow the garbage collector (GC)
One of the easier ways of implementing an event-driven programming model is through passing function pointers which are invoked when an event occurs. But because Java doesn’t support the notion











