循环用于打印字典字典

Question

I'd like to find a way to print a list of dictionnaries line by line, so that the result be clear and easy to read the list is like this.

---

myList = {'1':{'name':'x',age:'18'},'2':{'name':'y',age:'19'},'3':{'name':'z',age:'20'}...}

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and the result should be like this:

>>> '1':{'name':'x',age:'18'} 
    '2':{'name':'y',age:'19'}
    '3':{'name':'z',age:'20'} ...

Answer 1

Using your example:

>>> myList = {'1':{'name':'x','age':'18'},'2':{'name':'y','age':'19'},'3':{'name':'z','age':'20'}}
>>> for k, d in myList.items():
    print k, d

1 {'age': '18', 'name': 'x'}
3 {'age': '20', 'name': 'z'}
2 {'age': '19', 'name': 'y'}

---

More examples:

A list of dictionaries:

>>> l = [{'a':'1'},{'b':'2'},{'c':'3'}]
>>> for d in l:
    print d

{'a': '1'}
{'b': '2'}
{'c': '3'}

A dictionary of dictionaries:

>>> D = {'d1': {'a':'1'}, 'd2': {'b':'2'}, 'd3': {'c':'3'}}
>>> for k, d in D.items():
    print d  

{'b': '2'}
{'c': '3'}
{'a': '1'}

If you want the key of the dicts:

>>> D = {'d1': {'a':'1'}, 'd2': {'b':'2'}, 'd3': {'c':'3'}}
>>> for k, d in D.items():
    print k, d

d2 {'b': '2'}
d3 {'c': '3'}
d1 {'a': '1'}

Answer 2

>>> import json
>>> dicts = {1: {'a': 1, 'b': 2}, 2: {'c': 3}, 3: {'d': 4, 'e': 5, 'f':6}}
>>> print(json.dumps(dicts, indent=4))
{
    "1": {
        "a": 1, 
        "b": 2
    }, 
    "2": {
        "c": 3
    }, 
    "3": {
        "d": 4, 
        "e": 5, 
        "f": 6
    }
}

Answer 3

One more option - pprint , made for pretty-printing.

The pprint module provides a capability to “pretty-print” arbitrary Python data structures in a form which can be used as input to the interpreter.

List of dictionaries:

from pprint import pprint

l = [{'a':'1'},{'b':'2'},{'c':'3'}]
pprint(l, width=1)

Output:

[{'a': '1'},
 {'b': '2'},
 {'c': '3'}]

---

Dictionary with dictionaries in values:

from pprint import pprint

d = {'a':{'b':'c'}},{'d':{'e':'f'}}
pprint(d, width=1)

Output:

({'a': {'b': 'c'}},
 {'d': {'e': 'f'}})

Answer 4

myList = {'1':{'name':'x','age':'18'},
          '2':{'name':'y','age':'19'},
          '3':{'name':'z','age':'20'}}
for item in myList:
    print(item,':',myList[item])

Output:

3 : {'age': '20', 'name': 'z'}
2 : {'age': '19', 'name': 'y'}
1 : {'age': '18', 'name': 'x'}

item is used to iterate keys in the dict, and myList[item] is the value corresponding to the current key.