[C]增加了if的使用

Author: VincentJ

chapter4/If.py

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+cars = ['audi', 'bmw', "subaru", 'toyota']
+
+# if-elif-else--进入一个后不会再进另一个
+for car in cars:
+    if car == 'bmw':
+        print(car.upper())
+    elif car == 'audi':
+        print(car + ' is my car')
+    else:
+        print(car.title())
+
+# python是区分大小写的
+print(cars[-1] == 'bmw')
+# lower()和upper()是不会改变原值的
+print(cars[0].upper() == 'AUDI')
+
+# 判断不相等
+print(cars[-2].title() != 'subaru')
+
+# 多条件检查（与或）--and&or
+print((cars[0] == 'audi') and (cars[-1] == 'toyota'))
+print((cars[0] == 'audi') or (cars[-1] == 'subaru'))
+
+# 检测特定值是否在列表中
+print('audi' in cars)
+print('bmw' not in cars)
+
+# 确定列表是否为空
+teachers = []
+if teachers:
+    print("Have teachers")
+else:
+    print('Empty Array!')
+
+# 练习
+names = ['admin', 'lily', 'lucy', 'tom']
+if names:
+    for name in names:
+        if name == 'admin':
+            print('Hello admin, would you like to see a status report?')
+        else:
+            print('hello ' + name + ',thank you logging in again')
+else:
+    print('No names')