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Global variables should never be used with recursion. It leads to stack overflow and program crash. Recursion works well only if it is in a self contained unit, using local
Frequently the date format is mistakenly used in a SQL query of MS ACCESS. For example, when you want to make a query get records from May 1, 2000 in
A simple but effective MP3 Tag Editor written entirely in Visual Basic 6, and that consists of a DLL and a front-end application. What’s best is that you get the
Is server-side caching good or bad? This question can create many heated discussions. Since I’m from Sweden, I like what we call the golden middle course. We even invented a
t’s becoming common to retrieve data from a relational database formatted as a hierarchical XML document. By using an XML schema, it’s possible to generate data from XML documents and
CoInitialize() should be called for each thread in the application that makes COM calls. Not just once at application startup.
Many developers code text boxes to only accept numeric values. They usually forget about keyboard and mouse copy and paste functions. The following code only allows values 1 to 9
The AWT Component.paint and Component.update methods take a Graphics object as a parameter. This object should not be retained, because it might be a transient object valid only during the
The following code creates an array with month names or populates a combobox or listbox with same = without all the typing: holdMonth(1) =
Before I continue, I’d like to state up front thatnothing in this article should be construed as casting Windows 2000 / COM+ in anegative light. On the contrary, I’ve seen
Private Declare Function GetModuleFileName Lib “kernel32” Alias _ “GetModuleFileNameA” (ByVal hModule As Long, ByVal lpFileName As String, _ ByVal nSize As Long) As LongPrivate Declare Function GetModuleHandle Lib “kernel32” Alias
Private Function SystemParametersInfo Lib “user32” Alias _ “SystemParametersInfoA” (ByVal uAction As Long, ByVal uParam As Long, _ ByVal lpvParam As Any, ByVal fuWinIni As Long) As LongConst SPI_SETDESKWALLPAPER = 20′
Private Declare Function FormatMessage Lib “kernel32” Alias “FormatMessageA” _ (ByVal dwFlags As Long, lpSource As Any, ByVal dwMessageId As Long, _ ByVal dwLanguageId As Long, ByVal lpBuffer As String, ByVal
‘ Create a nested directory” This is similar to the MkDir command, but it creates any’ intermediate directory if necessarySub MakeDirPath(dirname As String) Dim i As Long, path As String
Private Declare Function SearchPath Lib “kernel32” Alias “SearchPathA” (ByVal _ lpPath As String, ByVal lpFileName As String, ByVal lpExtension As String, _ ByVal nBufferLength As Long, ByVal lpBuffer As String,
The System.exit method forces termination of all threads in the Java virtual machine. This can be drastic. It might, for example, destroy all windows created by the interpreter without giving
The following code prevents classes from serialization: public class MyClass implements Serializable{//you can write your code hereprivate void writeObject(ObjectOutputStream out) throws IOException{ throw new NotSerializableException();}private Object readObject(ObjectInputStream in) throws IOException,ClassNotFoundException{
The amount of time it takes to retrieve data blocks is proportionate to the number of extents in the table. Ideally, a table should have one to three extents. Run
The class JFileChooser inside javax.swing.* can be customized to display your own labels using the UIManager.put() method. It is a static method that takes an Object key (Original value) and
To eliminate duplicate values in a collection, Java provides it own API. HashSet (java.util.*) is the class which implements Set interface. import java.util.*;class Duplicate{ static void main(String[]arr){ HashSet set=new HashSet();
You may find that you want to know something about the form that contains the control you wish to use. You could do this by passing a reference to the
Visual Basic lacks the ability to make a file smaller without having to recreate it. But it is possible to use the SetEndOfFile API. Here is a function for it:
The following recursive function allows users to do an expand all via apopup menu: Public Sub ExpandAll(ByVal aNode As Node) Dim l_Counter As Long Dim l_Children As Long Dim temp_Node
One easy way to implement a generic name property of a class is to make a property procedure with TypeName function. Public Property Get Name() As String Name = TypeName(Me)End
My benchmarking shows that ToggleCase can crunch through a 2,000,000character string in under 4 seconds on a Pentium II. Public Function ToggleCase(ByVal strData As String) As String ‘This technique gets
The following code causes a somewhat cryptic warning message: struct Employee{ long ID; string name;};Employee emp;void func(int& id) { id=0;}// warning below issued for the following call:func(emp.ID);
To right justify the output of cout, call the width() function with the size of the output screen (in characters) as an argument. In the following example, the program calls
A header file should begin and end with #include guards to guarantee that it’s not #included more than once during the same compilation session. A typical #include guard looks as
It’s possible to use the format function to retrieve the decimal separator.Use the following statement: sTemp = Format(0,











