What are the delphi units? and the role of the unit

Because the shellexecute function exists in the file in the form of shellexecutea, and the shellapi unit is specially designed to handle the import of function macro alarms, so to use the api function, you need to refer to the shellapi unit. Of course, it's not that if you want to use the shellexecute function, you have to use the shellapi unit, you can use loadlibrary in the program to dynamically add the mask to the cover, and then find shellexecute to use, but this is too troublesome. As for the dry knowledge of which function is in which unit, the only way to do this is to check books and ask people at the beginning.

If you put it together, the speed of invocation will be greatly affected, although it is text, but it is too much ......

You don't have to learn it, but it will help you understand Delph a lot......

What to use, what to see, and what you want to understand requires a long time of accumulation.

For example, the definition of the classes system class, including tobject, tstringlist, etc.

Math units are related to mathematical calculations.

Graphic is all about graphics.

Variants are related to the content of the variant variable.

Forms are related to forms.

sysutils contains some commonly used functions and procedures dateutils related to dates.

Windows and Microsoft operating system related functions and messages and other content, detailed can see delphi help, said better than I understand.

Don't learn them all, you just need to know which unit a few commonly used functions are in, and you can refer to them when you use them, and it is recommended to look at Delphi's complete list of functions.

It's impossible to read them all at once, and it won't have any effect. In the development process, as long as you encounter one, you will learn one, and you will understand each point thoroughly, and you will find that the learning will be easier and easier!

Object-oriented concepts to understand.

If you are calling a function that comes with delphi.

Such as "max".

You can press "F1" on the function

Select "max function ...This one.

The help of the function is displayed.

Find the bold word "unit".

The underlined word "math" on the bottom line is the name of the unit where the function "max" is located.

All units, this one is too much to go.

Find out.

There are a lot of benefits to this, such as initializing static variables that don't have a chamber of interest. delphi for...delphi2009** Cheng has also advanced into the dry auspicious line and the improvement of the sedan chair.

There is an extra tmonitor in the system unit

1. Project documents (.)DPR) :d the Elphi project file, which is used to save the trust delay of forms, cells, etc., as well as the initialization of program runs, etc., which actually contains the pascal source. Wide eggplant plum.

2. Unit file (..)pas) :p ascal file, which is used to store the program source**, which can be a form-related unit or a stand-alone unit.

3. Form file (.)DFM): A binary file that holds the properties of a form or data module and its components.

4. Package source file (.)dpk): The project source file of the package, which is used to manage the packages information.

5. Resource files (.)res): This binary contains the project's icon, which is constantly updated and created by delphi and generally does not need to be modified by the user.

6. Backup file (.)-dp,.-df, -pa): Backup files corresponding to project, form, and unit files, respectively.

7. Desktop file (.)DSK): Contains information about the location of the Delphi window, files opened in the device, and other desktop settings.

8. Type library (.)TLB): A type that is built automatically or by a type library for OLE server-side applications.

9. Project configuration file (.)cfg): Saves the project configuration, with the same file name as the project name, but with a suffix. cfg。

10. Code Insight configuration file (.)DCI): Saves the modification information of Code Insight in the IDE.

11. Component plate configuration file (.)DCT): Saves the modification information of the component plate in the IDE.

12. Menu configuration file (..)DMT): Saves the IDE's modification information to the Delphi menu.

The container library modifies the file (DMT): Saves the program's modification information to the delphi menu container library.

Behavior list file (.)todo): Saves a list of behaviors for the current project. The file name is the same as the project name, but with a suffix. todo。

The following is the file that Delphi automatically creates after the program is compiled:

13. Execution file (.)exe): A Windows executable file compiled for the program.

14. Unit object file (..)dcu): is a compiled version of the unit file that is connected to the final executable file.

15. Dynamic connection library file (.)dll): A file created when designing a dynamic connection library.

16. ActiveX file (..)OCX): A special type of DLL that contains an ActiveX component or form.

1.First of all, consider that the call interface A is not much different from the function you want. Not much.

If there are too many, don't introduce the entire unit of it, because the interface change is a trivial matter, and the amount of that unit is too much, and other units may be introduced. So up, there will be a lot of mistakes, and you have to get rid of them little by little. It's troublesome.

Therefore, at this time, it is relatively simple to use the method of copying, that is, to open its form file, paste what you need, and then have a selective trade-off**. You can also refer to it**. But now it's not going to be a scramble.

2.If you really want to lead the whole unit forward. That's it.

1) Find a file under the directory folder. Copy all the ones with the A name, except for the ones with the wires, to your project file.

2) Open your project file, in delphi project-->add to project that is, the icon with the + sign on the toolbar, there is an icon.

3) At this point, this unit has been added to your project. Now it's time to remove the obstacles.

Don't understand what you mean? How much QQ do you have?

No, you open two delphi, the first one opens the interface project you want to copy, the second delphi creates a new project, or finds the from you want to copy from your own project, and then copies all the controls in the first delphi, and then pastes it in the second delphi, which is absolutely feasible.

In this way, only the controls and interfaces are copied, and you still have to add them yourself.

, to copy the past, and then project-->add to project.

This requires the inclusion of the called unit in this unit.

Utility functions are like this, you can create a new unit1 and use it to store utility functions and procedures.

Then make each form contain this cell, so that you can use the function or procedure inside.

The call should be made with the unit name. The format of the function, (

Idea 1 Define the public variable public ss:string, and add uses unit2 to unit1

2 The output value of the test in another unit (unit2) is assigned to ss;

3 The button of unit unit1, when called, take ss

To prefix test() with unit2 or form2

Write on or you try.