An assignment expression can appear inside an if condition: if (x = getval() ) { // do someting } The if condition is evaluated in two steps: first, the unconditional

A derived class’s member-initialization list can initialize any non-ambiguous member of its class, including base subobjects. Suppose you have a class C that is derived from B, which is in

By default, a typedef name declared in the global scope has internal linkage. This means that separately compiled source files can’t refer to a typedef declared in another source file,

An equality expression takes two operands, the second of which is often a constant or an rvalue: if (x==4) // 4 is an rvalue // .. do something if (y!=MAX_COUNT)

Question: If I try to open an Informix table in Microsoft Visual InterDev, which uses SCO Vision Ultralite ODBC driver on an NT4/SP4 IIS4 Web server, Visual InterDev hangs. Using

Question: I am trying to insert a string into a char(500) but get this error message: A quoted string exceeds 256 bytes. I’m using this for a Web site built

Question: I am receiving an error code of 0400 when a program is executing. I have been told that this is an SQL error code; however, none of the books

Question: I have been running Informix 7.22.TC1 successfully on Windows NT servers with the WebLogic 1.1 JDBC driver. On Web server restart, my application suddenly shows an error in connection

You can use this JavaScript to get confirmation from the user before navigating to another page. Redirect Related Posts Avoid NPE via JDK 8, OptionalCheck Whether a String Contains Another

Question: I am trying to update an Access database with an ASP page. My ASP page contains a guest book with first name, last name, and other relevant text boxes.

Question: When declaring an unbounded array in my function’s parameter list, int a[], can I use the sizeof() operator to determine the array’s length at runtime? Answer: No, you can’t

Question: Is there anyway to have a variable number of arguments passed to a macro? Yes, I know it can be done with inline, but this is for debugging purposes.

Question: How do sessions work with clustered NT servers? How do you make use of clustering technology if an NT machine goes down along with its sessions? Is NT smart

A proxy server reduces the amount of time spent retrieving documents over the Internet. It does this by caching, or storing, the document in memory and then serving it from

I write apps for companies where computer know-how is at an all-time low. Most applications scare people to death. However, Web-style forms and graphic buttons present soothing enough interfaces that

You can use MSFlexGrid for data entry without using additional ActiveX controls. For this, use the KeyPress and KeyUp events. To use the MSFlexGrid for data entry, add the grid?named

Another useful STL algorithm is reverse(). This algorithm reverses the order of elements in a specified sequence. reverse() takes two iterators that mark the sequence’s beginning and end, respectively. Here

I researched Windows Script Components (WSC) and was interested in their capability to integrate with ASP. I tried integrating a VB DLL with ASP. I included a reference to the

Here’s a function that converts a decimal number (base 10) to another base number system. Each digit position corresponds to a power of N, where N is a number between

It was a question of time until a C++ virtual machine would appear. Implementing a Java-style virtual machine for C++ is a trivial task. The problem is that such a

Isolating the source of an error in a method containing many nested method calls can be difficult. If you haven’t written comprehensive error-handling code in every method and property you

In the following template member function, the parameter T can be a class or a built-in type: void vector< T >::resize (size_type new_size) { T val; // oops! What if

I’ve been working on a class module called clsDateInfo that returns various properties of a given date, and using it in some monthly trend graphs. I had to come up

An incomplete array declaration can appear in a function’s parameter list. For example: int count(const char s[]); The declaration of s doesn’t include the array’s size. Can count() use the

This useful code listing prevents users from entering duplicate entries into a listbox or modifying existing listbox entries. While the code prevents users from adding duplicate entries, you can modify

Recently, I turned to Windows messaging to manipulate certain dialogs by simulating button clicks programmatically. I looked through my API references and found only the WM_LBUTTONDOWN and WM_LBUTTONUP messages. I

Many VB programmers haven’t harnessed the power of VB6’s resource editor. They still use traditional LoadPicture or other primitive calls to load bitmaps and icons. Before VB5, loading pictures into

The type qualifiers const and volatile are idempotent. This means that if a type qualifier is included indirectly several times in a type specification (e.g., through a typedef or a

I’m developing a database system for a distant customer with a slow Internet connection. The system imports data and generates reports. The problem with importing and generating reports is that,