擅长:python、mysql、java
<pre><code>class globalVsLocal_1:
def f1(self):
global a #this is to reference a variable declared in the global context.
print ("f1 a = %s"%(a)) # if global a was not declared in the first line, generates this line an error as variable a not defined is
a = a + 10
print ("f1 a = %s"%(a))
def f2(self):
print("f2 a = %s"%(a))
def f3(self):
print("f3 b = %s"%(b))
#b = b + 1 #activating this line will yield an error. Because the absence of the keyword global. the print statement works immaculately without global keyword because it just reads the value without
#manipulate it
print("f3 b = %s"%(b))
def g1(self):
def g2():
print("g2 b = %s "%(b))
g2()
a = 1
b = 20
obj = globalVsLocal_1()
obj.f1()
obj.f2()
obj.f3()
obj.g1()
</code></pre>
<p>调用g2时缺少缩进。
这将提供以下输出</p>
<pre><code>f1 a = 1
f1 a = 11
f2 a = 11
f3 b = 20
f3 b = 20
g2 b = 20
</code></pre>