The Latest

DevX - Software Development Resource

The Representation Of Pointers To Members

Although pointers to members behave very much like ordinary pointers, behind the scenes, they are not necessarily represented as pointers. In fact, a single pointer to member usually consists of

DevX - Software Development Resource

Declaring Pointers to Member Functions

Pointers to member functions consists of the member function’s return type, the class name followed by ::, the pointer’s name, and the function’s parameter list. For example, a pointer to

DevX - Software Development Resource

Returning an Argument by Reference

Question: What exactly returns a C++ function if it returns an object by a reference like: Person& GetNextPerson(); Please explain at assembly level, if possible. Answer: Assembly speaking, such a

DevX - Software Development Resource

Open ODBC Connection Without Hardcoding Password

Question: In my ASP page, I open an ODBC connection with: Set Conn = Server.CreateObject(“ADODB.Connection”)Conn.CommandTimeout = 600Conn.open “Database_name”,”Username”,”password”. How can I avoid hardcoding the password in the ASP source? Answer:

DevX - Software Development Resource

Data Source Name Not Found Error ‘80004005’

Question: What does this error message mean? Microsoft OLE DB Provider for ODBC Drivers error ‘80004005’ [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified /SampleProject/default.asp,

DevX - Software Development Resource

Overloading istream operator >> for bool

Question: I am trying to overload the istream operator >> to work with type “bool”. From my point of view the code looks okay, except the VC++ 6.0 compiler tells

DevX - Software Development Resource

Cross Platform Compilers

Question: Is there a C++ compiler that I can use to go cross-platform with development?I need to develop the same DLLs for AS400, Sun, and Windows. Answer: I’m not sure

DevX - Software Development Resource

Are Borland’s Delphi and C++Builder code-similar?

Question: I am trying to decide between purchasing Borland’s Delphi or C++Builder. Can the VCL code written to work in Delphi also work in C++Builder (latest versions for both)? Answer:

DevX - Software Development Resource

C++ Comments

Question: Why isn’t C commenting style preferred in C++? C commenting style definitely looks neater and more readable than the C++ commenting style. Answer: /* comments in C++ are just

DevX - Software Development Resource

Accessing Arrays

Question: Normally, you access an array by the number of the element you want. Is it possible, in C++, to access an element by the value and return the number?

DevX - Software Development Resource

Display Date and Time of File Upload

Question: How can I display the date and time a file was uploaded to my Web server using ASP? Answer: If you can access the file from an ASP page,

DevX - Software Development Resource

Updating a VB6 DLL on the Web Server

Question: We have Internet Information Server (IIS) 4.0 running Active Server Pages (ASP) with a Visual Basic 6.0 DLL serving data content to the ASP pages. The problem lies when

DevX - Software Development Resource

Dynamically Insert Text Into a Text Box

Question: How can I provide the user with a combo box and based on his selection populate the data in a text box? The data has to come from a

DevX - Software Development Resource

Understanding Session_OnStart and Application_OnStart

Question: I am confused regarding the Application_OnStart and Session_OnStart events in the global.asa file. What I feel is that the application_onstart event is triggered the very first time the application

DevX - Software Development Resource

Connect to a Remote Database Using ASP

Question: How do I connect to an Access database that resides on a network server other than the Web server? My goal is to query the Access database and display

DevX - Software Development Resource

Overloading The ! Operator

Question: Is it possible to have a postfix version of the ! operator? Answer: No, you cannot alter the associativity, ordering and position of built-in operators when you create an

DevX - Software Development Resource

Cannot Call API Functions From ASP

Question: Can I use Windows API calls in ASP? If so, do I have to declare functions? Answer: Unfortunately, at this time you cannot call API functions from ASP. The

DevX - Software Development Resource

Access Data From SQL Server in ASP

Question: I’m using Microsoft SQL Server 6.5, Active Server Pages (ASP), and ActiveX Data Objects (ADO). When I retrieve a string with a value of “New York” from the table

DevX - Software Development Resource

Access Violation

Question: I get an “Access violation at address…” error, when I run my program. An error occurs on line “scanf(…)” but I can’t figure out what is wrong. Answer: In

DevX - Software Development Resource

Overload Operator []

Question: Is it possible to overload the ‘subscripting operator’ [] so it will take char * as the index, similar to an array? For example: I want to write a

DevX - Software Development Resource

Compiler Warnings with STL Map Containers

Question: Using even the most basic default constructor, such as ” mapm; ” , causes a debug error creating huge compiler warnings in Visual C++ and MS Visual Studio 6.0.

DevX - Software Development Resource

Equivalent functions for Unchecked Conversion

Question: Are there any functions/libraries that can perform the Unchecked_Conversion function in Ada? We are writing a program that will read a bitstream. Upon determining the type, we want to

DevX - Software Development Resource

Pointer Arithmetic

Question: I am a programmer beginning to learn C++. I wrote this chunk of code: /////////////////////////////////////////////////////////////// Get to do some pointer arithmetic!/////////////////////////////////////////////////////////////#include #include const char NL = ‘ ‘;const char

DevX - Software Development Resource

Keep Your IIS Browser Definitions Current

Internet Information Server includes a component that helps you determine the capabilities of a browser before you send code that may not be supported. The list of capabilities is stored

DevX - Software Development Resource

Escape Your Apostrophes in JavaScript

In JavaScript, the apostrophe (‘) is a string delimiter. That is, it marks the beginning or end of a text string. If you include an apostrophe inside a string, the

DevX - Software Development Resource

Add Some Pseudo-Class to Your HTML

Rollover effects are fun in HTML but too much code and alternate images means your page takes longer to render in the browser. Don’t forget that some effects are built

DevX - Software Development Resource

Interface Usage

Question: In designing a program, how do I know when to use an interface or a class?Is there a basic rule to follow? Answer: Java supports a limited form of

DevX - Software Development Resource

Color Space Transformation

Question: How do I transform the color space of an image?from its original space to grayscale, for instance? Answer: The ColorSpace class is defined in the java.awt.color package.It encapsulates the

DevX - Software Development Resource

String to StringBuffer Conversion

Question: How do I convert a String object to a StringBuffer object? I tried to put a String object into a stringBuffer using a cast, but I got an invalidcast