شی
Class
A class may be defined either in
گامباس as e.g. the class "
TextBox"
or the programmer creates a new own class.
A class never has an address. A class cannot be displayed.
Object
To use a class at runtime, it must be instantiated. By this an object is created.
This is either done by the framework at start, or by the program with the
/lang/new2 command.
In both cases some memory holds all the variables of the class.
Objects have a runtime address. This address can be displayed in the watch window.
As well members of the object can be displayed in the watch window.
Examples
In this example "
TextBox" is a class.
"TextBox1" is an object, which is created by the IDE.
"xTextBox1" is a reference to an object of the type
TextBox.
Later in this example the reference to the IDE created "TextBox1" is copied to "xTextBox1".
In the watch window of the IDE both references show the same hexadecimal address.
As well members of the object can be displayed in the watch window.
|
Expression
|
Value
|
|---|
|
TextBox
|
ERROR: Unknown ...
|
|
TextBox1
|
(TextBox 0x81099c0)
|
|
xTextBox1
|
(TextBox 0x81099c0)
|
|
xTextBox1.Text
|
"Set xTextBox1"
|
مثال
PUBLIC SUB Button1_Click()
DIM xTextBox1 AS TextBox ' can hole the address of the object
xTextBox1 = TextBox1 ' gets the address of the already existing object
xTextBox1.Text = "Set xTextBox1"
xTextBox1.X = TextBox1.X + 80
xTextBox1.Y = TextBox1.Y + 120
END
In this example "
TextBox" is a class. "xTextBox1" is an object of this class, which will be created new on the
Form Form1.
And then filled with a Text and moved to a place somewhere relative to the IDE created
TextBox with the name TextBox1
PUBLIC SUB Button1_Click()
DIM xTextBox1 AS TextBox ' can hold the address of the object
xTextBox1 = NEW TextBox(Form1) ' Instatiate a TextBox, create the object
xTextBox1.Text = "Set xTextBox1"
xTextBox1.X = TextBox1.X + 80
xTextBox1.Y = TextBox1.Y + 120
END
> def > object 
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