GENERAL KNOWLEDGE[]
It would be a good idea to buy a Delphi book, to help you learn ObjectPascal syntax. Delphi programs are written using ObjectPascal. The basics for VB programmers:
- line termination with semicolon: every statement must end with a semicolon.
- assignment: You use colon-equals, like this: a := 1;
- comparison: you can only use the equals without the colon, in comparisons, such as within an if statement: if (a=3) then doSomething;
- variable types: Learn to use the basic ObjectPascal data types: Integer, Double, String, etc.
- global variable declaration: You use the var section of a unit (a unit is a source code file) to declare globals
- local variable declaration: you use the var section of a method or procedure or function to declare local variables
- various control structures: familiarize yourself with for loops, while loops, if then else, and other control structures.
- blocks with begin and end: familiarize yourself with the usage of begin and end.
- object oriented programming: You should get used to object oriented programming, declaring and instantiating classes, and that kind of thing. A book helps out here. VB6 is not truly object oriented. Learn what that means. Unlearn damage caused by VB.
- the Delphi Visual Component Library (VCL): familiarize yourself with the most common things you'll need to deal with in any VCL program, such as TForm, TButton, TListbox, TCombobox, TMemo, TEdit, and so on.
FAQs[]
| VB6 | Delphi | Comments | |
|---|---|---|---|
| DoEvents | Application.ProcessMessages | ||
| Control arrays | N/A | Delphi doesn't handle controls in the same way. Control arrays are essentially a "hack" to do some of the things that can easily be done in Delphi through a good object-oriented framework (VCL). For example, Delphi allows you to create components on the fly - something that would require control arrays in VB. | |
| (see one approach to implementing "control arrays" in Delphi here: BDN Code Central Submission #15860) | |||
| MsgBox | MessageDlg and ShowMessage | ||
| Dim | Var | Variable defination |
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