文件的增删改查

#author:徐征
def look():
    while 1:
        x=input('查看：如www.oldboy.org
').strip()
        n=[]
        flag=False
        with open("haproxy.conf",encoding="utf8") as f_read:
            for line in f_read:
                if line.startswith("backend") and x in line:
                    flag=True
                    continue
                if line.startswith("backend") and flag:
                    break
                if flag:
                    n.append(line.strip())
            for i in n:
                print(i)
def delete():
    x=input('删除：如www.oldboy.org
').strip()
    with open("haproxy.conf",encoding="utf8") as f_read,open("test",mode="w",encoding="utf8") as f1_read:
        for line in f_read:
            f1_read.write(line)
            if line.startswith("backend") and x in line:
                break
def increase():
    x = input('修改：如www.oldboy.org
').strip()
    i="        server 11111 weight 2222 maxconn 3333"
    with open("haproxy.conf", encoding="utf8") as f_read, open("test", mode="w", encoding="utf8") as f1_read:
        for line in f_read:
            f1_read.write(line)
            if line.startswith("backend") and x in line:
                f1_read.write(i)
                break
def add():
    x = input('增加：如www.oldboy.org
').strip()
    i = "        server 11111 weight 2222 maxconn 3333,
"
    with open("haproxy.conf", encoding="utf8") as f_read, open("test", mode="w", encoding="utf8") as f1_read:
        for line in f_read:
            f1_read.write(line)
            if line.startswith("backend") and x in line:
                f1_read.write(i)
def msg():
    xzh='''
    *******************************
     1.look 查看
     2.delete 删除
     3.increase 修改
     4.add  增加
     0.exit 退出
    ******************************* 
    '''
    print(xzh)
def mains():
    msg()
    while 1:
        q = int(input("必须输入0,1,2,3,4这四个数字
输入需要使用的功能编号--->:"))
        if q==0:
            print("再见！")
            exit()
        if q==1:
            look()
        if q==2:
            delete()
        if q==3:
            increase()
        if q==4:
            add()
mains()