Python3 List index() Method

Description

The index() function is used to find the index position of the first matching item of a value in a list.

Syntax

Syntax of the index() method:

list.index(x[, start[, end]])

Parameters

x -- The object to be searched for.
start -- Optional, the starting position for the search.
end -- Optional, the ending position for the search.

Return Value

This method returns the index position of the searched object. If the object is not found, an exception is raised.

Examples

The following examples demonstrate how to use the index() function:

Example 1

#!/usr/bin/python3

list1 = ['Google', 'Example', 'Taobao']
print ('Example index value is', list1.index('Example'))
print ('Taobao index value is', list1.index('Taobao'))

The output of the above example is as follows:

Example 索引值为 1
Taobao 索引值为 2

Example 2

#!/usr/bin/python3

list1 = ['Google', 'Example', 'Taobao', 'Facebook', 'QQ']
# Start searching from a specified position
print ('Example index value is', list1.index('Example',1))