源代码1

1

#关于try和except的语法
file_name = input('请输入需要打开的文件名:')
f = open(file_name)
print('文件的内容是：')
for each_line in f:
    print(each_line)

2

#关于try和except、finally的语法
try:   #检测范围
    sum = 1 + '1'
    f = open('我为什么是个文件.txt')
    print(f.read())
    f.close()
except OSError:
    print('文件错误\n错误的原因是：' + str(reason))
except TypeError as reason:
    print('类型错误\n错误的原因是：' + str(reason))

3.

try:   #检测范围
    
    f = open('a.txt','w')
    print(f.write('我存在'))
    sum = 1 + '1'
    f.close()
except (OSError,TypeError):
    print('文件错误')
finally:
    f.close()
    

4.

def showMaxFactor(num):
    count = num // 2
    while count > 1:
        if num % count == 0:
            print('%d最大的约数是%d'%(num,count))
            break
        count -= 1
    else:
        print('%d是素数！'% num)
num = int(input('请输入一个数：'))
showMaxFactor(num)

5.

'''try:
    int('abc')
except ValueError as reason:
    print('出错误了：' + str(reason))
else:
    print('异常')
'''

try:
    int('123')
except ValueError as reason:
    print('出错误了：' + str(reason))
else:
    print('异常')

6.

try:
    with open('data.txt','w') as f:
        f.write('我爱你')
        for each_line in f:
            print(each_line)
except OSError as reason:
    print('出错了')
finally:
    f.close()