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Never Store Arrays of Objects in an auto_ptr

The Standard Library’s auto_ptr class template automatically destroys an object that is allocated on the free store when the current scope is exited. For example: #include //definition of auto_ptr#include using

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Add a Hyperlink Listener in Java

To add a hyperlink listener in Java, add it to the JEditorPane and set its contents. A lot of errors may be thrown, but this is how the hyperlink listener

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Dump the Server Variables to a Table With ASP Code

The Active Server Pages Request object gathers lots of information about the server and the browser. This information is stored in the ServerVariables collection. You can iterate through the entire

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The Default Value Returned From main()

In this example, main() is missing an explicit return statement. int main() { printf(“hello world”); } In C, when control reaches the end of main() without encountering a return statement,

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Create ODBC DSNs Dynamically

You can use Visual Basic to create ODBC Data Sources Names (DSNs) dynamically for MS SQL Server. Simply place this line in a module: Declare Function SQLConfigDataSource Lib “odbccp32.dll” (ByVal

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Avoid Empty Exception Handlers

One of the most frustrating experiences when running a Java program is an empty line where you expect information about a thrown exception. The programmer probably meant to catch the

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Netscape Displays a Blank Page

Question: My Web page works fine using Internet Explorer but if view with Netscape it displays a blank page. I think it has something to do with the table commands,

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Make a Cursor Appear in First Form Field

Question: When designing a form, like a login page, how do I make the cursor automatically sit in the first form field? For example, I ask for an admin number

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Pre-Fill a User Form

Question: I’d like to implement a script on my Web site that I’ve seen on other sites. This script asks visitors to register for free through a form as a

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Delete an Item From Favorites

Question: How do I delete an item from Favorites under Windows NT 4.0? Answer: Under Windows NT 4.0, the favorites are saved in this folder: C:WINNTProfilesFavorites You can delete items

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The Size of an Enum Type

In C, the size of an enumeration equals the sizeof(int). In C++, the underlying type for an enumeration is not necessarily an int–it can be smaller. Furthermore, if an enumerator’s

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Invoking Methods Using Reflection

The java.reflect package enables a Java program to invoke methods on classes using the string names of the methods. This feature is the basis of the interaction between a Java

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Start MS SQL Server Dynamically

Use this code in your C++ executable to start MS SQL Server dynamically on aWindows NT machine. Link to w95scm.lib, which is provided with the SQL 7.0 CD. #include “wn95scm.h”

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Two Conundrums Associated With Inline Functions

Two conundrums are associated with inline functions. The first has to do with maintenance. A function can begin its life as a slim inline function, offering the benefits that are

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Compiling a Large Number of Files With JDK 1.1

Using the javac utility provided with the Java Development Kit (JDK) 1.1.x to compile a large number of source files often fails with an OutOfMemoryError. To avoid this error, you

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Concatenate to Increase ASP Performance

Although it is common to use repeated Response.Write statements in an Active Server Pages script, you may not be getting the most out of your Web server. Each time you

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Passing a parameter to an external function

Question: Can I pass the address of a PowerBuilder function as an argument to an external function located in a dll? The dll documentation shows that it expects the address

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64-bit integer support

Question: How can I support 64-bit integers on a 32-bit system? I need to do division on numbers exceeding 4.3 billion. I have the resaults in a char value, and

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Copy objects

Question: Assume that you have a class Distance and two objects dist1 and dist2. You have initialized the object dist1. Now you do: Distance dist2(dist1) to create a copy of

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Data Files Help

Question: I am teaching an introductory C++ course at thehigh school level. My textbook briefly coversdata files–sequential access–but doesn’t provide many examples of how to write/read multiple variables. Where would

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DOS to Windows Conversion

Question: How do I convert a DOS file into a Windows program? Answer: Unfortunately, not very easily. While DOS programs will run under Windows and you may also want to

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Resizing Dynamic Array

Question: int num = 50;int **stuff;stuff = new int* [num];for (int i = 0 ; i < num ; ++i) stuff[i] = new int [num]; The code above is copied

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Derived Classes

Question: Functions are inherited easily. But if you have a variable in the base class and you want have the same variable but with a different type in the derived

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Visual C++ Check/Radio Buttons

Question: How does one go about disabling/enabling buttons and check boxes in dialogs based on the state of other buttons or check boxes? The controls in question are of the