Python中三种命令行参数利用方式详解

print("程序名：",sys.argv[0])
print("第一个参数：",sys.argv[1])
print("第二个参数：",sys.argv[2])
print("第三个参数：",sys.argv[3])

if len(sys.argv) < 2:
    print("usafe: python sysArgv.py filename")
    sys.exit()

filename = sys.argv[1]
try:
    with open(filename,'r') as f:
        print(f.read())
except:
    print("文件不存在")
    sys.exit()

import sys
import getopt

opts,argv = getopt.getopt(sys.argv[1:],'-u:-p:',["file="])
print("opts输出结果为：",opts)
print("args输出结果为：",argv)

import sys
import getopt

def usage():
    print('-h: --help 帮助;')
    print('--file=文件名')

def read(filename):
    try:
        with open(filename, 'r') as f:
            print(f.read())
    except:
        print("文件不存在")
        sys.exit()

def start(argv):
    file = ""
    if len(argv)<1:
        print("-h 获取帮助信息")
        sys.exit()
    opts, argvs = getopt.getopt(argv, '-h', ["file="])

    for opt,arg in opts:
        if opt == "-h":
            usage()
        elif opt == "--file":
            read(arg)

if __name__ == '__main__':
    start(sys.argv[1:])

import optparse

def start():
    usage = "python %prog -u/--user <target user> -p/--password <target password>"
    parser = optparse.OptionParser(usage)
    parser.add_option('-u', '--user', dest='User', type='string', help='target user', default='root')
    parser.add_option('-p', '--password', dest='Pwd', type='string', help='target password')
    options, args = parser.parse_args()

    print("用户名为", options.User)
    print("密码为", options.Pwd)

if __name__ == '__main__':
    try:
        start()
    except KeyboardInterrupt:
        print("interrupted by user, killing all threads...")

import optparse
import sys

def read(filename):
    try:
        with open(filename, 'r') as f:
            print(f.read())
    except:
        print("文件不存在")
        sys.exit()

def start():
    usage = "python %prog -u/--user <target user> -p/--password <target password> -f/--file <target file>"
    parser = optparse.OptionParser(usage)
    parser.add_option('-u', '--user', dest='User', type='string', help='target user', default='root')
    parser.add_option('-p', '--password', dest='Pwd', type='string', help='target password')
    parser.add_option('-f','--file', dest='Filename',type='string',help='write report to FILE', metavar='FILE',default='123.txt')
    print(parser.parse_args())
    options, args = parser.parse_args()

    print("用户名为", options.User)
    print("密码为", options.Pwd)
    print("文件为",options.Filename)
    # for option,arg in parser.parse_args():
    #     if option.Filename == '-f':
    read(options.Filename)

if __name__ == '__main__':
    try:
        start()
    except KeyboardInterrupt:
        print("interrupted by user, killing all threads...")

import argparse

'''
argparse.ArgumentParser().add_argument参数：
1、可以设置多个选项字符串，比如上面的'-u','--user'这两个，用的时候任选其一；
2、type用于检测命令行输入参数的数据类型是否符合要去，有string、int、float等类型；
3、dest=用于定义选项存放的位置，作为后面的第一个字典（options）的键，值为命令行输入的参数；
4、help用于定义帮助信息；
5、default设置默认值
'''
parse = argparse.ArgumentParser()
parse.add_argument('-u', '--user', dest='User', type=str, help='target user', default='root')
parse.add_argument('-s','--sex',dest='Sex',type=str,choices=['男','女'],default='男',help='target sex')
parse.add_argument('-n','--number',dest='Num',required=True,type=int,default='target two number')
print(parse.parse_args().User,parse.parse_args().Sex,parse.parse_args().Num)

import sys,argparse

def read(filename):
    try:
        with open(filename, 'r') as f:
            print(f.read())
    except:
        print("文件不存在")
        sys.exit()
def start():
    parse = argparse.ArgumentParser()
    parse.add_argument('-u', '--user', dest='User', type=str, help='target user', default='root')
    parse.add_argument('-s','--sex',dest='Sex',type=str,choices=['男','女'],default='男',help='target sex')
    parse.add_argument('-n','--number',dest='Num',required=True,nargs=1,type=int,default='target two number')
    parse.add_argument('-f','--file',dest='File',type=str,default='123.txt')
    print(parse.parse_args().User,parse.parse_args().Sex,parse.parse_args().Num,parse.parse_args().File)
    read(parse.parse_args().File)
if __name__ == '__main__':
    start()