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Timely Capture of Font Metrics

If you extend an AWT class to add text to a GUI component, then you probably need access to the font’s metrics so that you can deduce the amount of

Directing CGI Output to Another Frame

A little-known attribute of the tag is TARGET. This attribute can be used to direct the output of a CGI program to another browser window, or another frame in the

Determining Shift Button State

Question: How can I determine if is down or up while dragging an object within my app? The goal is to detect if something is being copied or moved. Answer:

Developing E-Mail System

Question: I want to develop a free e-mail system similar to what Hotmail and Yahoo offer. I was wondering if you could give me some ideas on how to approach

STL Containers Should Not Hold auto_ptr<> Members

During reallocation, a container re-constructs its elements in a new memory location and destroys the original elements by invoking their destructor. Since the destructor of auto_ptr deletes its bound object,

Using Files as Persistent Flags

In Java, static variables may be used as flags to maintain state between different instantiations of a class (see Tip: “Using Static Variables to Store State Across Instantiations”). However, the

NT as Primary Domain Server

Question: I want to set up my NT Server as my primary domain server. How do I do it? Answer: Unfortunately, the only way I know to convert a current

MTS, ASPs, and State(less) objects

Question: When implementing the Microsoft DNA model, it is suggested to create objects with methods only (no properties) to maintain true stateless objects. If an object will only live for

16 bits vs 32 bits

Question: Can we transfer an application from 32 bits to16 bits (PowerBuilder 5.0) without problems ? Answer: The only thing you will have to check for is API calls. The

Parsing a comma-delimited text file

Question: Is there an easy way to load a datastore with a comma-delimited text file? Answer: Yes, just load the file into memory and do a global search and replace

Querying NT

Question: Is there a way to query NT 4.0 (programmatically or manually) to have it tell me whether it is NT workstation or NT server? Is the answer in the

Exporting dw to Excel using OLE using PB5

Question: I’m trying to export a report to Excel with OLE automation. I’m using PB 5.0.2 and Excel 97. I’ve seen countless examples on how to do this (in fact,

Adding DOS exe

Question: How do I add a DOS exe such as ping to a VB program? Answer: If starting another program is what you want, then use the Shell function. The

GetWindowsDirectory API 16 bit to 32 bit

Question: I have migrated an application from 5.0.03 to 6.5 and continue to get this error when pressing the Run button: Error – 14 – Error opening DLL library kernel.exe

Adding local groups to a NT Workstation

Question: I am trying to write an app that can add local groups to the NT security database on an NT workstation. When I use the netlocalgroupadd() function, I get

CopyFile API fails with AT command

Question: I have a program that copies a file from Network Drive W: to Local Hard Drive E: using the CopyFile API Function. From the command line, the program works

The Case for Class Variables

When each instance of a class needs access to a value that can vary from one run of the applet or application to the next, but will be constant within

Keep Visual InterDev 6 Out of Your DE Connection Strings

Users of Visual InterDev 6 have reported frustrating problems in configuring their data connections while using the Data Environment (DE). Even though you manually edit the Application variables and connection

Handling Checked Exceptions

There are three ways to deal with checked exceptions in Java. First, you can declare that the “callee” method throws them (using the “throws” keyword). You should do this when

Mouse click

Question: How do I make the mouse click in VB 4? It just auto clicks without user inputs in the spot the mouse currently is. Answer: Without having to go

ADODB.connection

Question: I use ADO with an Oracle database. To get the connection I have to use: dim Adodb as New ADODB.connectionwith Adodb .connectionString = ???? .openend with What do I

Text in VB5

Question: I’m a beginner to Visual Basic, and I would like to display in a text box several lines of text. However, when I enter the code under the command

Disable Textboxes and Combo boxes

Question: When a textbox or combo box is disabled, the black text within these control becomes grey. I would like to have all the features of disabling these controls, but

Use External JavaScript Files

If you have the same JavaScript program appearing on several different Web pages, you might want to consider using an external file. That way all the pages can refer to

Creating Files Using FileOutputStream

You accomplish basic file I/O in Java using data streams. The most basic file I/O operations in Java use the functionality offered by these classes: FileInputStreamFileOutputStream If you’re new to

The Underlying Representation of NULL

C and C++ define NULL differently: #define NULL 0; // A typical definition of NULL in C++ #define NULL ((void*)0) // C defines NULL this way Why is it defined