Original: http://www.cnblogs.com/GavinDai/archive/2011/10/24/2222735.htmlWe are in the program design, always use the definition of variables and the declaration of variables, but sometimes we are not very clear about the concept, know how it is
1, can local variables and global variable duplicate?
A: Yes, the local will screen the overall situation. To use a global variable, you need to use the "::"
Local variables can have the same name as global variables, and when referenced within a
Discussion on defining variables and variable priorities in JavaScript and javascript
See the following code:
Copy codeThe Code is as follows:If (! ("Aa" in window )){Alert ('Oh my God ');Var aa = 1;}Alert ("aa" in window );Alert (aa );
Answer the
The shell supports custom variables.Defining variablesWhen defining a variable, the variable name does not have a dollar sign ($), such as:
VariableName="value"
Note that there can be no spaces between the variable name and the equals
Operating system1, what is the operating system The operating system is located between the computer hardware and the application software is a control program that coordinates, manages and controls computer hardware resources and software
Definition and initialization of C + + struct type
It is sometimes necessary to combine different types of data into an organic whole for easy user use. The data of these combinations in a whole are interrelated. For example, a student's number,
In fact, the variables have been used many times in the previous example. The amount of value that can be changed while the program is running is called a variable. A variable should have a name and occupy a certain storage unit in memory, where the
We are in the program design, always use the definition of variables and variable declarations, but sometimes we are not very clear about the concept, know how it is used, but do not know how to do, the following I simply put their differences are
Differences between variable definition and Declaration
(Reprinted)
In program design, we always use the definition of variables and the declaration of variables. Sometimes we are not very clear about this concept and know how to use it, but I don't
Item 26: variable definitions (variable definition) is postponed whenever possible)
By Scott Meyers
Translator: fatalerror99 (itepub's nirvana)
Release: http://blog.csdn.net/fatalerror99/
If you define a variable with a constructor (constructor) or
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