擅长:python、mysql、java
<p>当函数返回一个值时,必须将它赋给一个要保留的值。函数内部定义的变量(如下面示例中的<code>b</code>)<strong>只存在于函数内部,不能在函数外部使用</p>
<pre><code>def test(a):
b=a+1
return b
test(2) # Returns 3 but nothing happens
print b # b was not defined outside function scope, so error
# Proper way is as follows
result=test(2) # Assigns the result of test (3) to result
print(result) # Prints the value of result
</code></pre>