Everyone doesn't misunderstand. It is not a soldier, but it is not a soldier, but it is the Chinese translation of the INPRISE's signature product! Introducing Delphi's article has been much more, is everyone who suffer from its powerful development function? Visual programming has made many friends a dream. Indeed, several controls are equipped with several statements, maybe a software is coming out. But is you not satisfied with the components of using others? Want to know more about Windows programming? Replacement Master Delphi? OK, please continue to look down.
The INT21H under DOS is important for the development of the DOS program, and for the development program under Windows, it is necessary to understand the API function. Components are like moving, and the API function is like a heart, with a deep internal force, then learning the move is easy. Therefore, the more API functions you have mastered, the more likely it be a Delphi master, even Windows programming masters. Therefore, both C , VB or Delphi has no exception to support the API function call, C and Delphi are fully supported API functions, and VB only supports some API functions (there are many parts of some. , Especially the Delphi call API function is most convenient, and has reached the realm of the API function, call the API function and almost the same. Below I will explain the use of the API function in Delphi in detail, I will write a small example of each statement, so that everyone can understand how it is used. If you carefully read this article, I believe that everyone will have a deeper understanding of Delphi programming. But don't take halfway, afraid of fear, remember: For those who want to practice, there must be hard work! Learn to program, can not play games, can't get a FPE cheating.
(1) Controls and message functions
1 Syntax: annpopup: bool;
Unit: windows.pas (this unit Delphi will be in Uses, below)
Role: Judgment Whether there is any pop-up window on the screen
Return Value: BOOL, Returns true if there is a pop-up menu
Note: For this function, the pop-up menu contains all visible tolerance top-level windows, regardless of pop-up or overlapping windows
Example:
Procedure TFORM1.BUTTON1CLICK (Sender: TOBJECT);
Begin
IF (AnyPopup) THEN
Label1.caption: = 'Pop-Ups Found: True'
Else
Label1.caption: = 'Pop-Ups Found: false';
END;
2 Syntax: EnableWindow (hwnd: hwnd; Benable: Bool): BOOL; Unit: Windows.Pas
Role: All mouse and keyboard input are allowed or prohibited in the specified window.
Return Value: Bool, if it is true, Windows has been disabled, otherwise returns false
Example:
Procedure TFORM1.BUTTON1CLICK (Sender: TOBJECT);
Begin
IF (ISWindowenabled (Edit1.Handle) THEN
Begin
EnableWindow (Edit1.Handle, False);
Button1.caption: = 'enable window'; edit1.text: = 'this window is disabled';
end
Else
Begin
EnableWindow (Edit1.Handle, True);
Button1.caption: = 'disable window';
Edit1.Text: = 'this window is enabled';
END;
END;
3 Syntax: FlashWindow (hwnd: hwnd; binvert: bool): bool;
Unit: Windows.PAS
Role: Blink Displays the specified window. This means that the title and instructions of the window will change, and it seems to switch from the activity to the non-active state, or switch in reverse. Usually apply this function to the inactive window, causing the attention of the user
Return Value: BOOL, if the window is active before calling, return True
Note: This function is usually used in combination with a counter to generate a continuous flicker.
In Windows NT and Windowsfor Workgroup, Binvert parameters are ignored.
But will not ignore in Windows 95
Example:
Procedure TFORM1.TIMER1TIMER (Sender: TOBJECT);
Begin
FlashWindow (Form1.Handle, True);
FlashWindow (Application.handle, True);
END;
4 Syntax: setWindowText (hwnd: hwnd; lpstring: pchar): BOOL;
Unit: Windows.PAS
Role: Set the contents of the title text or control of the window
Return Value: Set successfully returns true, otherwise returns false
Example:
Procedure TFORM1.BUTTON1CLICK (Sender: TOBJECT);
VAR
Thet: pchar;
TEXTLEN: Integer;
Begin
TEXTLEN: = getWindowTextLength; Form1.Handle;
GetMem (THETEXT, TEXTLEN);
GetWindowText (Form1.Handle, ThetExt, Textlen 1);
Edit1.text: = String (ThetExt);
FreeMem (Thetxt);
END;
Procedure TFORM1.BUTTON2CLICK (Sender: TOBJECT);
Begin
SetwindowText (form1.handle, pchar (edit1.text));
END;
5 Syntax: IsWindow (hwnd: hwnd): BOOL;
Unit: Windows.PAS
Role: Determine if a window handle is valid
Return Value: Returns True effectively, otherwise return FALSE
Example:
Procedure TFORM1.BUTTON1CLICK (Sender: TOBJECT);
Begin
IF (iswindow (Button1.Handle) THEN
Button1.caption: = 'True'
Else
Button1.caption: = 'FALSE';
END;
How, still addictive? Today is the first time, introduce some functions that are easily acceptable, otherwise friends will definitely call. Don't you know that your friends can accept this form of arrangement? Also, I will introduce according to the classification of the API function (control and message function / hardware and system function / menu function / text and font function / print functions, etc., I will not introduce all API functions, otherwise it is The suspicion of the scam fees, and I have an example of each statement, only the usual use of usually used, sometimes introducing the API function that is more secure but very useful. With TIPS (Delphi Tips):
If there is such a directory:
C: /Windows/media/temp/abc/sound/chime.wav
I hope it can shorten:
C: / windows /../ Sound / Chime.wav
How to write the program?
Reply:
Try with the following procedure:
Function ShortenFileName (S: String): String;
VAR Drive, Curdrive: String [2];
Dir, Curdir: String [80];
Name: String [20];
EXT: STRING [5];
i: byte;
Begin
For i: = 1 to length (s) do s [i]: = Upcase (s [i]);
S: = fEXPAND (S);
FSPLIT (S, DIR, NAME, EXT);
Drive: = COPY (DIR, 1, 2);
DIR: = COPY (DIR, 4, Length (DIR) -3);
Getdir (0, Curdir);
Curdrive: = COPY (Curdir, 1, 2);
Curdir: = COPY (Curdir, 4, Length (Curdir) -3) '/';
if Drive = Curdrive Then Begin
IF Copy (Dir, 1, Length (Curdir) = Curdir Then Begin
I: = Length (Curdir);
If Length <> I THEN DIR: = DIR '/';
ShortenFileName: = COPY (DIR, I 1, Length (DIR) -i-1) Name EXT;
END ELSE ShortenFileName: = COPY (S, 3, Length (s) -2);
ELSE ShortenFileName: = S;
END;
Note: This article is only written to improve Delphi's ability to write, non-general entry-level tutorial, so all Delphi's own functions and some basic skills in the text will no longer explain, ask friends to check the Delphi online help manual.
