#读文本文件 read(n)读n个字符 read()读整个文本 n>实际个数，读取实际个数 如果已经读到文件尾部了，再度返回空串
#遇到\n \r \r\n作为换行标识，并统一转换为\n作为文本输入换行符
def writeFile():
fobj=open("./student.txt","wt")
fobj.write("abc\nxyz")
fobj.close()
def readFile():
fobj=open("./student.txt","rt")
s=fobj.read()
print(s)
fobj.close()
try:
writeFile()
readFile()
except Exception as err:
print(err)
def writeFile():
fobj=open("./student.txt","wt")
fobj.write("abc\nxyz")
fobj.close()
def readFile(n):
fobj=open("./student.txt","rt")
s=fobj.read(n)
print(s)
print(len(s))
fobj.close()
try:
writeFile()
n=520
readFile(n)
except Exception as err:
print(err)
#如果文件指针已经到了文件的尾部，再读就返回一个空串
def writeFile():
fobj=open("./student.txt","wt")
fobj.write("ab c\nxyz")
fobj.close()
def readFile():
fobj=open("./student.txt","rt")
flag=1
st=""
while flag==1:
s=fobj.read(1)
if s!="":
st=st+s
else:
flag=0
fobj.close()
print(st)
try:
writeFile()
readFile()
except Exception as err:
print(err)
#读取一行的函数readline
#readline()一直读到'\n'或文件尾为止
#如果读到'\n',那么返回的字符包含'\n'
#如果到了文件尾部，再次就读到一个空字符串
def writeFile():
fobj=open("./student.txt","wt")
fobj.write("abc\nxyz")
fobj.close()
def readFile():
fobj=open("./student.txt","rt")
s=fobj.readline()
print(s,"length=",len(s))
s=fobj.readline()
print(s,"length=",len(s))
s=fobj.readline()
print(s,"length=",len(s))
fobj.close()
try:
writeFile()
readFile()
except Exception as err:
print(err)
#一行一行读取文件数据
def writeFile():
fobj=open("./abc.txt","wt")
fobj.write("abc\nxyz")
fobj.close()
def readFile():
fobj=open("./abc.txt","rt")
goon=1
st=""
while goon==1:
s=fobj.readline()
if s!="":
st=st+s
else:
goon=0
fobj.close()
print(st)
try:
writeFile()
readFile()
except Exception as err:
print(err)
#读取所有行的函数readlines一般和for配合使用
def writeFile():
fobj=open("./abc.txt","wt")
fobj.write("abc\neee\nxyz")
fobj.close()
def readFile():
fobj=open("./abc.txt","rt")
# print(fobj.readlines())#['abc\n', 'eee\n', 'xyz']
for x in fobj.readlines():
print(x,end='')
fobj.close()
try:
writeFile()
readFile()
except Exception as err:
print(err)
#读取保存在student.txt文件学生信息
class student:
def __init__(self,name,gender,age):#构造函数
self.name=name
self.gender=gender
self.age=age
def show(self):#类函数
print(self.name,self.gender,self.age)
students=[]
try:
f=open("student.txt","rt")
while True:
name=f.readline().strip("\n")#将一行的前后/n字符去掉
if name=="":
break
gender=f.readline().strip("\n")
age=float(f.readline().strip("\n"))
students.append(student(name,gender,age))#类放入students
f.close()
for s in students:
s.show()
except Exception as err:
print(err)
