A case analysis of true,false condition judgment in Python

The examples in this paper describe the usage of true,false conditional judgment in Python. Share to everyone for your reference. The specific analysis is as follows:

Programmers with programming experience know the wording of conditional statements:
Take C + + as an example:

The code is as follows:

if (condition)
{
DoSomething ();
}

The syntax for conditional judgments in Python is as follows:

The code is as follows:

if (condition):
DoSomething ()

So when is the condition in the conditional statement true and false?
In high-level languages such as C++/java, the condition is false if the value of the condition is 0 or if the referenced object is a null pointer.
In Python if condition is ", (), [],{},none,set () then the condition is flase, otherwise true.
The following is a test statement for Python:
1. Testing for strings

The code is as follows:

>>> condition= '
>>> print ' True ' if condition Else ' False '
False
>>> condition= ' Test '
>>> print ' True ' if condition Else ' False '
True

2. Testing for the original group

The code is as follows:

>>> condition= ()
>>> print ' True ' if condition Else ' False '
False
>>> (condition=)
>>> print ' True ' if condition Else ' False '
True

3. Testing for the list

The code is as follows:

>>> condition=[]
>>> print ' True ' if condition Else ' False '
False
>>> condition=[' A ', ' B ']
>>> print ' True ' if condition Else ' False '
True

4. Testing for Dictionaries

The code is as follows:

>>> condition={}
>>> print ' True ' if condition Else ' False '
False
>>> condition={' k ': ' V '}
>>> print ' True ' if condition Else ' False '
True

5. Test for None

The code is as follows:

>>> Condition=none
>>> print ' True ' if condition Else ' False '
False

6. Test for Set ()

The code is as follows:

>>> Condition=set ()
>>> print ' True ' if condition Else ' False '
False
>>> Condition.add (' a ')
>>> print ' True ' if condition Else ' False '
True

Hopefully this article will help you with Python programming.

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