How to Add user input to a Dictionary in Python

# Add user input to a dictionary in Python

To add user input to a dictionary in Python:

1. Declare a variable that stores an empty dictionary.
2. Use a range to iterate N times.
3. On each iteration, prompt the user for input.
4. Add the key-value pair to the dictionary.

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employees = {}

for i in range(3):
    name = input("Enter employee's name: ")
    salary = input("Enter employee's salary: ")

    employees[name] = salary


# 👇️ {'Alice': '100', 'Bob': '100', 'Carl': '100'}
print(employees)

The code sample prompts the user for input 3 times and adds each key-value pair to the dictionary.

The example uses the range() class to prompt the user for key-value pairs.

The range class is commonly used for looping a specific number of times in for loops

If you only pass a single argument to the range() constructor, it is considered to be the value for the stop parameter.

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print(list(range(3))) # [0, 1, 2]

print(list(range(5))) # [0, 1, 2, 3, 4]

The range starts at 0 and goes up to, but not including the specified number.

Note that the input() function always returns a value of type string.

If you need to add an integer value to the dictionary, use the int() class to convert the string to an integer.

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employees = {}

# 👇️ converting to integer with int()
salary = int(input("Enter employee's salary: "))

employees['salary'] = salary

# 👇️ {'salary': 100}
print(employees)

# Add user input to a dictionary using a while loop

You can also use a while loop if you want to make sure the dictionary has a length of at least N key-value pairs.

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employees = {}

max_length = 3

while len(employees) < max_length:
    name = input("Enter employee's name: ")
    salary = input("Enter employee's salary: ")

    employees[name] = salary


# 👇️ {'Alice': '100', 'Bob': '100', 'Carl': '100'}
print(employees)

If the dictionary has a length of less than 3, we keep prompting the user for input.

# Preventing the user from adding the same key to the dictionary

This approach is especially useful when you want to make sure the user doesn't enter the same key twice.

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employees = {}

max_length = 3

while len(employees) < max_length:
    name = input("Enter employee's name: ")
    salary = input("Enter employee's salary: ")

    # 👇️ Check if the key not in the dict
    if name not in employees:
        employees[name] = salary


# 👇️ {'Alice': '100', 'Bob': '100', 'Carl': '100'}
print(employees)

The in operator tests for membership. For example, k in d evaluates to True if k is a member of d, otherwise it evaluates to False.

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my_dict = {
    'id': 1,
    'name': 'Bobby Hadz',
    'salary': 500,
}


print('name' in my_dict)  # 👉️ True
print('another' in my_dict)  # 👉️ False

k not in d returns the negation of k in d.

When used with a dictionary, the operators check for the existence of the specified key in the dict object.

# Add user input to a dictionary using split()

You can also use the str.split() method to add user input to a dictionary.

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employees = dict(
    input('Enter key and value separated by space: ').split()
    for _ in range(2))


# 👇️ {'id': '1', 'name': 'Alice'}
print(employees)

The example expects that the user enters space-separated keys and values.

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print('name Alice'.split()) # ['name', 'Alice']

The str.split() method splits the string into a list of substrings using a delimiter.

The method takes the following 2 parameters:

We used a space separator in the example, but you can also use a comma if the values of the dictionary contain spaces.

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employees = dict(
    input('Enter key and value separated by space: ').split(',')
    for _ in range(2))


# 👇️ {'id': '1', 'name': 'Alice'}
print(employees)

The code sample is similar to the previous one, however, we used a comma as the separator instead of a space.

This is useful because the values of the dictionary might contain spaces.

I've written a detailed guide on converting a comma-separated string to a dictionary in Python.

# Additional Resources

You can learn more about the related topics by checking out the following tutorials:

• How to take a List from user input in Python
• How to check if User Input is Empty in Python
• Using a For or While Loop to take user input in Pythono- Taking user input boolean (True/False) values in Python
• How to Create a Date from user Input in Python
• Taking a file path from user input in Python
• How to take Float user input in Python
• Multiple lines user Input in Python
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• Creating a Tuple or a Set from user Input in Python
• How to Validate user input in Python
• Yes/No question with user input in Python
• How to save user input to a File in Python
• Using user input to Select an Option from a List in Python