Python總結第二篇之if else and 循環

Python 的if else 結構其實比較簡單，複雜的地方其實應該算是和其他的操作合併在一起。先拋開其他的來說，只是看if else，後續會再介紹關於其他的操作，比如字符串。話不多說，直接上實例。

結構

if x == 1 and y == 1:
	print x+y
elif x > 1 or y < 1:
	print x
elif line == False:
	print "default"

in / not in

target = "123XXXYYYZZZ"
pattern = "XXX"
noise = "CCC"

if pattern in target:
	print pattern
if noise not in target:
	print noise

輸出結果:

XXX
CCC

循環 + if else

# for 循環
target = "test.txt"
file = open(target)

for line in file:
	if x == 1 and y == 1:
		continue
	elif x > 1 or y < 1:
		break
	elif line == False:
		print "default"
		
file.close()
"""
while 循環
"""
while True:
	if x == 1 and y == 1:
		continue
	elif x > 1 or y < 1:
		break
	else:
		print "default"