Python - Convert String Truth values to Boolean

Converting string truth values like "True" and "False" into their corresponding boolean values in Python is a straightforward yet useful operation. Methods such as dictionaries, direct comparison, and built-in functions offer simple and efficient ways to achieve this transformation for various use cases.

Using eval() Function

eval() function in Python is used to evaluate a string as a Python expression and convert it into the corresponding object

s = "True" # Convert string to boolean using eval boolean_value = eval(s) print(boolean_value) 

True 

Explanation :

• eval(s) function evaluates the string s as a Python expression, converting it into its corresponding Python object, in this case, the boolean value True.
• The result, stored in boolean_value, is then printed, showing the evaluated boolean value True.

Using str.lower() with Comparison

Using str.lower() with comparison allows you to convert a string to lowercase before performing a case-insensitive comparison. This ensures that the comparison ignores differences in letter casing between the two strings.

s = "True" # Convert string to boolean by comparing lowercase value boolean_value = s.strip().lower() == "true" print(boolean_value) 

True 

Explanation :

• s.strip().lower() method first removes any leading or trailing spaces using strip(), then converts the string to lowercase using lower(). This ensures the comparison is case-insensitive.
• The string is then compared to "true", and if they match, the result is True; otherwise, it is False. The result is stored in boolean_value and printed.

Using a Dictionary for Lookup

Using a dictionary for lookup allows you to map specific string values to corresponding boolean values or other types. This provides an efficient way to perform case-insensitive or custom comparisons by leveraging the dictionary's key-value pairs.

s = "False" # Dictionary to map string values to boolean bool_map = {"true": True, "false": False} # Convert string to boolean using the dictionary boolean_value = bool_map.get(s.strip().lower(), False) print(boolean_value) 

False 

Explanation :

• The bool_map dictionary maps the lowercase string values "true" and "false" to their corresponding boolean values True and False.
• The s.strip().lower() converts the input string to lowercase and removes any extra spaces, then bool_map.get() retrieves the corresponding boolean value, defaulting to False if the string doesn't match. The result is stored in boolean_value and printed.