Functions:raw_input () and input ()
Note: In python3.x, the Raw_input () has been removed, instead of input (), which is only renamed, and the usage is the same. So here is the introduction of raw_input () and input () in python2.x, as long as the Raw_input () is used in python3.x.
1: Function: Read the console input and user implementation interaction
2: Grammar
Raw_input ([prompt])
Input ([prompt])
3: Parameters
Prompt: If this parameter is present, it will be output directly to the screen and will not go down another line
4: The relationship between the two:
Input () is essentially implemented using raw_input (), which calls the Eval () function after Raw_input () is called, and is called as follows:
def input (prompt):
Return (eval (raw_input (prompt)))
5: The two points are the same:
can accept strings, numbers, and expressions as input.
6: The difference between the two:
6.1. When input is a string:
Raw_input (): reads the console input while returning the string type
Input (): reads the input from the console, but must be enclosed in quotation marks when entering, otherwise it will be an error.
6.2. When the input is a pure number:
Raw_input (): Reads the console input and returns the string type as String processing
Input (): Reads the console input, returns the input numeric type (int, float)
6.3. When the input is a string expression:
Raw_input (): reads the input from the console, but does not operate on the input numbers, directly returning the string type as String processing
Input (): reads the input from the console, evaluates a valid Python numeric expression, and returns the result of the operation
6.4, the input for special characters
Like ' \ t ', ' \ n ', etc.
Raw_input (): reads input from console, returns string type, same as input
Input (): reads the input from the console, but must be enclosed in quotation marks to return the content represented by the special symbol
Note: It is recommended to use Raw_input () to interact with users without special requirements
7: Example:
7.1. When entering as a string:
>>> A1 = Raw_input ("raw_input_str:") raw_input_str:hello>>> print a1,type (A1) Hello <type ' str ' >>>> A2 = input ("INPUT_STR:") Input_str:hellotraceback (most recent call last): File "<pyshell#4> ", line 1, in <module> a2 = input (" Input: ") File" <string> ", line 1, in <module>nameerror:name ' Hello ' is not defined>>> a2 = input ("INPUT_STR:") input_str: ' Hello ' >>> print a2,type (A2) Hello <typ E ' str ' >
7.2. When the input is a pure number:
>>> B1 = Raw_input ("raw_input_int:") raw_input_int:123>>> print B1,type (B1) 123 <type ' str ' > >>> B2 = input ("Input_int:") input_int:123>>> print B2,type (b2) 123 <type ' int ' >
7.3. When entering as a string expression:
>>> C1 = Raw_input ("raw_input_exp:") Raw_input_exp:3 + 3>>> print C1,type (C1) 3 + 3 <type ' str ' >&G t;>> C2 = input ("input_exp:") Input_exp:3 + 3>>> print c2,type (C2) 6 <type ' int ' >
7.4, the input for special characters when:
>>> D1 = raw_input ("raw_input_sp:") raw_input_sp: \t>>> print d1,type (d1) \ t <type ' str ' >> >> D2 = input ("input_sp:") input_sp: \ttraceback (most recent call last): File "<pyshell#57>", line 1, in <module> d2 = input ("input_sp:") File "<string>", line 1 \ t ^syntaxerror:unexpected Character after line continuation character>>> D2 = input ("input_sp:") input_sp: ' \ t ' >>> print d2,type ( D2) <type ' str ' >
Python raw_input () and input () functions read Interactive input
