Why Loop Through a Dictionary?

In Python, you can loop through a dictionary to:

• Get keys
• Get values
• Get key-value pairs

Example 1: Loop Through Keys

person = {
 "name": "Alice",
 "age": 25,
 "city": "New York"
}
for key in person:
   print(key)

Output:

name
age
city

Explanation: Looping directly over the dictionary returns its keys

Example 2: Access Values Using Keys

person = {
 "name": "Alice",
 "age": 25,
 "city": "New York"
}
for key in person:
   print(person[key])

Output:

Alice
25
New York

Explanation: Use person[key] inside the loop to get the corresponding value.

Example 3: Use .values() to Loop Through Values

person = {
 "name": "Alice",
 "age": 25,
 "city": "New York"
}
for value in person.values():
   print(value)

Output:

Alice
25
New York

Explanation: .values() returns all the values in the dictionary.

Example 4: Use .keys() to Loop Through Keys Explicitly

person = {
 "name": "Alice",
 "age": 25,
 "city": "New York"
}
for key in person.keys():
   print(key)

Output:

name
age
city

Explanation: .keys() is similar to the default loop, but explicit.

Example 5: Use .items() to Loop Through Key-Value Pairs

person = {
 "name": "Alice",
 "age": 25,
 "city": "New York"
}
for key, value in person.items():
   print(f"{key}: {value}")

Output:

name: Alice
age: 25
city: New York

Explanation: .items() returns key-value pairs, which can be unpacked in the loop.

Example 6: Conditional Logic While Looping

person = {
 "name": "Alice",
 "age": 25,
 "city": "New York"
}
for key, value in person.items():
   if key == "age":
       print("Age found:", value)

Output:

Age found: 25

Explanation: You can add if conditions inside the loop to check for specific keys or values.

Summary Table

Conclusion

Looping through dictionaries is essential when you need to access or process key-value data. Use .items() for pairs, .keys() or default for keys, and .values() for values.