Several methods of string splicing in python and their advantages and disadvantages.

1. Use the + operator

This is the most direct way, by+Operators to concatenate strings.

Example:

str1 = "Hello"
str2 = "World"
result = str1 + " " + str2
print(result)  # Output: "Hello World"

Pros and cons:

• advantage: The grammar is simple and intuitive and easy to understand.
• shortcoming: If there are more strings spliced, the efficiency is lower. Each splicing creates a new string object because strings are immutable in Python.

2. Use the join() method

join()Methods are often used to splice multiple strings (usually strings in lists or tuples) into one string. It is the recommended method for string stitching, especially when stitching multiple strings.

Example:

words = ["Hello", "World"]
result = " ".join(words)
print(result)  # Output: "Hello World"

Pros and cons:

• advantage: High efficiency, especially when multiple strings are to be spliced,join()Will compare+The operator is more efficient because it will only generate a new string object.
• shortcoming: You need to first put the string to be spliced ​​into an iterable object (such as a list or tuple).

3. Use f-string (format string literals)

Starting with Python 3.6,f-stringProvides a concise string interpolation method, which allows you to insert variables directly into strings.

Example:

name = "Alice"
age = 30
result = f"My name is {name} and I am {age} years old."
print(result)  # Output: "My name is Alice and I am 30 years old."

Pros and cons:

• advantage: Concise, easy to read, easy to debug. Ideal for inserting variables.
• shortcoming: Applicable to Python 3.6 and above only.

4. Format using %

This is a commonly used string formatting method in Python and can still be used in Python 3. It passes placeholders (e.g.%s、%detc.) to format the string.

Example:

name = "Bob"
age = 25
result = "My name is %s and I am %d years old." % (name, age)
print(result)  # Output: "My name is Bob and I am 25 years old."

Pros and cons:

• advantage: The syntax is relatively simple and can be used quickly for simple formatting.
• shortcoming: For complex formatting or splicing of multiple variables, the code may become less readable.

5. Use  ()

This is a standard formatting method in Python 2.7 and Python 3, providing more flexibility.()Methods can be made through placeholders{}To specify the variable to be inserted.

Example:

name = "Charlie"
age = 28
result = "My name is {} and I am {} years old.".format(name, age)
print(result)  # Output: "My name is Charlie and I am 28 years old."

Pros and cons:

• advantage:Compare%More flexible, supports various methods such as position parameters, keyword parameters, etc., and the code is clearer.
• shortcoming: The grammar is relatively long and is moref-stringIt's a little more complicated.

6. Use StringIO (for efficiently splicing large number of strings)

When you need to splice a large number of strings, you can use. It is an in-memory file object suitable for scenes where strings are spliced ​​multiple times. This method is more efficient when dealing with large numbers of strings.

Example:

from io import StringIO

output = StringIO()
("Hello")
(" ")
("World")
result = ()
()
print(result)  # Output: "Hello World"

Pros and cons:

• advantage: When multiple splicing of strings are required,StringIOis a more efficient way to avoid creating new string objects every time you splice it.
• shortcoming: relatively complex and suitable for scenarios where string splicing is large.

7. Use list and append() (suitable for splicing large number of strings)

If you need to splice a large number of strings, you can add them to a list and usejoin()Let’s splice it once.

Example:

words = []
("Hello")
("World")
result = " ".join(words)
print(result)  # Output: "Hello World"

Pros and cons:

• advantage: More than directly used+Operators are more efficient, especially when splicing multiple strings, avoiding creating new string objects every time they splice.
• shortcoming: Need to use a list, which is slightly verbose in syntax.

Summarize

By choosing the right method, string splicing can be made efficient and meet your needs.

The above is a detailed explanation of the several methods of string splicing in python and the advantages and disadvantages. For more information about python string splicing, please pay attention to my other related articles!