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Question: In my program, the user must log in. I must take that login and search a database to see if the login is valid and then match a password
On some platforms, the default font used by Java for menu text is unfortunately not the user-selected, system-wide menu font. With some VMs it can be undesirably small. You can
When laying out a dialog box with a manager that does not provide space between the components and the edges of the box (such as a GridLayout manager), the following
Question: How can I dynamically create a web page from an FTP directory listing of files with a particular extension? Answer: While there are sophisticated components (.DLLs) that you could
The dynamic_cast operator may convert an object to another related (derived or a base) object at run-time. When it fails to convert a pointer to the target pointer, it returns
When a data member is declared mutable, then it is legal to assign a value to it from a const member function. The following example may demonstrate when it is
The advantages of a string object over a C-style char* are obvious. Yet there are times you may still need a null-terminated char*, for example, when legacy C code is
Whenever your class uses a type-field, as in the following case: class Internl { //internationalization aid Lang lg; //type field FontResource fonts public: enum Lang {English, Hebrew, Danish} Internl(Lang lang)
Here is useful code for a generic routine to load a grid from anSQL statement. The example shown is for RDO and Sheridan’s grid,but works with minor modification for any
If you are rolling your own controls in VB5 to support applications dealing with databases, consider putting a “Valid” property, “Validation” event, and a “Required” property on your controls. The
Question: Using an Editmask on a date field, PowerBuilder does not allow a date greater than 12/31/2999. We would like to allow users to enter a ‘high date’ of 12/31/9999
Question: Can you have more than one JavaScript per page? If so, how do you do it? Answer: Yes. You can have more than one script block per page as
Question: How do I insert a row in a drop-down datawindow in PowerBuilder? Answer: You need to use a function of the datawindow control called GetChild. This function returns a
Question: We have an application that uses Powertool as a class library. We want to move to PFC. Do you have any suggestions on how to accomplish this task? Is
Question: How can I simply turn a monotonous 2-D table into a 2-D chart representation using JavaScript language? Or do I have to use Java for this purpose? Answer: Sorry.
Question: Where can I find a good book or good doccumentation on Visual InterDev 6.0? Answer: As you’ve discovered, the online Help is disabled in the Visual InterDev March Pre-release.
Question: I know that the multimedia API is limited in the Windows CE environment, but is there any other way to control the audio device? What I want is to
Question: Can someone help with identifying/deciphering the hex instruction 0x70fd2b7b of JavaScript into a corresponding command? My application randomly causes the IE4 browser to crash. The instruction is always the
A constructor taking a single argument is by default an implicit conversion operator: class C { int I; //… public: C(int i);//constructor and implicit conversion operator //as well }; void
When initializing objects data members by a mem-initializer list, the compiler transforms the list into the order of the declaration of the data members in that class: class A {
The use of malloc() and free() functions in a C++ file is not recommended and is even dangerous: 1. malloc() requires the exact number of bytes as an argument whereas
If your class contains other object(s) as members, you should initialize the embedded object(s) in a mem-initializer list instead of assigning their values inside the class constructor: class Person {
All member functions implemented within a class declaration are by default inline: //file: A.hclass A { int a; public: int Get_a() { return a; } //declaration + definition; //implicitly inline
When working on developing or debugging an app that is created via automation (i.e. ActiveX DLL), keep in mind the following: if you invoke that app from a calling program
Be aware that the VB IDE hijacks the registry settings for your public classes when working on projects such as ActiveX DLLs and Controls. The IDE will temporarily replace (in
When passing a variant array by reference, make sure to use Dim to declare the statement before using Redim. Example: Private Sub Command1_Click()Dim x as integer ReDim v(2) As Variant
When you have multiple web pages calling the same client script code, locate the shared script code in a separate file (e.g. Shared1.js) and reference the shared code in each
You can change the types of files recognized by the DevStudio editor by adding the file type to the following registry key: HKEY_CURRENT_USERSoftwareMicrosoftDevStudio5.0IstudioProjectEditors For example, to allow JavaScript source files
Fast, Efficient and Easy Way to Initialize Local ArraysBy default, local data arrays created on the stack are not initialized; they contain garbage values. The easiest, most efficient and future-proof
Assigning an object to itself is disastrous, so whenever you have to define a copy constructor and assignment operator, make sure your code is guarded from such a mistake: class


