Python类型转换

Question

I try to iterate over some number using Python 3. To do so I thought about casting the number to string. Simplified version is here:

def printValue(num):
    value = str(num)
    for i in len(value):
        print(value[i])
    return;

However though I get info that int is not iterable:

Traceback (most recent call last):                                                                                                                                                                                                
  File "main.py", line 9, in <module>                                                                                                                                                                                             
    print(printValue(12112121))                                                                                                                                                                                       
  File "main.py", line 5, in printValue
    for i in len(value):                                                                                                                                                                                                          
TypeError: 'int' object is not iterable  

What do I do wrong?

Answer 1

len returns an integer, and you can't iterate over an integer.

If you want to iterate over the range of integers from 0 up to len(value) , use range .

for i in range(len(value)):

Although in this case you don't really need the indices, so you may as well just iterate directly over the string's characters.

for c in value: