Since 1998, DevX has helped people start businesses, build websites, and provide enterprise technology to people globally. Interviewing the likes of Microsoft’s co-founder, Steve Ballmer, the publication brings comprehensive, reliable, and accessible insights to the Internet.
The “Auto-Propercase Text Box at Entry” tip [VBPJ May 1997, page 63] has a simpler solution. The StrConv function can propercase any string. You can achieve the same effect with
While developing a database front end for hand-tool management, I discovered a need to handle both fractional and decimal representations of dimensions in the same text box. This makes it
When you define a form named MyForm, Visual Basic creates one instance with the name “MyForm.” Many programmers confuse this special instance with other instances created using Dim. For example,
Question: We want to begin collecting customer e-mail addresses from our Web site. Our current file system is mainframe based, storing all data in uppercase format. Are e-mail addresses case
Question: In my Visual Basic ActiveX DLLs, some of the methods that I created for my objects use optional parameters. When I attempt to call these methods, I receive a
Question: I have noticed that some sites have tables that sit side-by-side. I can never duplicate this behavior with my HTML scripts. Do you have any suggestions? Answer: Positioning two
A type-name is merely a placeholder that has to be substituted with a proper type. For example: template T min( const T& first, const T& second); //T is a type-name,
To decide when it is safe to exit your program, use a DataUnsafe function. Set the DataModified variable to False when you load or save data, or when you start
Question: I’m trying to query our Human Resources database to find the number of temporary employees in each department. I’m using the following SQL statement: select count (*)from employeewhere status
Question: I have a table like this: name cat1 cat2—- —— —–A 1 orangeA 1 orangeB 1 appleB 1 appleB 1 appleC 2 bananaC 2 bananaC 2 bananaC 2 banana
Question: Is there any other way apart from using the INSERT INTO command that allows you to append a line to a database? I have a primary key “ID,” but
Question: I am working with a client that has a Powerbuilder application. We need to call that app through a variety of APIs. The client says that they cannot act
Question: How can I dynamically add a visual userobject to a visual userobject? The PB documentation mentions how to add a userobject to a window at run-time, but not how
Question: I have a select query “Select * from Table where ID in (8, 2,3,78,32,1,7)” that I want returned in the same order that the IDs are in in the
Question: I need to know how to order by the count of the selected field. For example: Select xxx count(xxx)from prod-tableorder by xxxI’d like to order/rank field xxx highest to
Question: Is there a limit to the number of connections to an SQL server? If so, how many connections are permitted at one time? Answer: The number of connections is
Question: Is there a way to title report outputs in SQL? Answer: If you are creating a quick and dirty report, you can always add a title simply by putting
Question: I have been asked as a SQLServer DBA to certify SQLServer 6.5 as Y2K compliant, apart from any statements from Microsoft. I am aware that Microsoft indicates that all
Question: I want to filter out data from a datawindow during runtime. I have a sle-field in which the user enters a search string (for example, “SM”). This should be
Question: Can I print only one page in datawindow? Answer: Yes, you can set the print range of a datawindow, just like in Word or Excel. If you set the
Question: I am building a VB/SQL database app in which I need to control access to individual records in a table based on an EmployeeId. The front-end VB app requires
Question: How can I display the row number in the results of a SELECT query? For example: Select empname from employees where city = “toronto” I would like to show
Question: Is there a limit on the number of tables that can be joined in SQL? Answer: In SQL Server version 6.5 there is an upper limit of 16 tables
Question: What does the PL stand for in PL/SQL? Answer: The PL stands for procedural. SQL is traditionally set-oriented. In many situations, a significant amount of procedural code must also
Question: I have a problem making reports flexible. Let us assume we have a standard report, but it changes according to the situation. How can I allow users to change
Unlike ordinary member functions, a virtual destructor is not overridden when redefined in a derived class. Rather, it is extended: the lower-most destructor first invokes the destructor of its base
A template definition can be #included in several translation units (source files). However, each time it is #included the definition is recompiled. Using large template definitions can increase compilation time
In some rare cases, it is useful to disallow further derivation of a class. Classes that implement system API or sensitive security management are good examples for that. Declaring the
C++ defines a hierarchy of standard exceptions that are thrown at run time when abnormal conditions arise, such as when operator new fails. The standard exception classes are derived from
The preprocessor #include directive appears in two flavors: #include < vector > // angular brackets and #include “myclass.h” // quotes The two are not interchangeable. The angular-bracket version applies to

