Python 从字符串创建列表，在逗号处拆分

我目前正在从事一个项目，该项目从一个文件中输入以下信息：

10015, John, Smith, 2, 3.01
10208, Patrick, Green, 1, 3.95
10334, Jane, Roberts, 4, 3.81

我需要做的是分割这些信息，分别存储每个值，然后根据用户需要将其打印到屏幕或文件中

应拆分然后分配信息的功能如下：

def fetchRecord( self ):
    #Read the first line of the record.
    line = self._inputFile.readline()
    line = input.split( ', ' )
    if line == "":
        return None

    #If there is another record, create a storage object and fill it
    student = StudentRecord()
    student.idNum = int( line[0] ) 
    student.firstName = line[1]
    student.lastName = line[2]
    student.classCode = int( line[3] )
    student.gpa = float( line[4] )
    return student

我当前收到的错误如下：

builtins.ValueError: invalid literal for int() with base 10: '10015, John, Smith, 2, 3.01\n'

我调用的整个代码是：

class StudentFileReader:
#Create new student reader instance.
def __init__( self, inputSrc ):
    self._inputSrc = inputSrc
    self._inputFile = None

#Open a connection to the input file.
def open( self ):
    self._inputFile = open( self._inputSrc, "r" )

#Close the connection to the input file.
def close( self ):
    self._inputFile.close()
    self._inputFile = None

#Extract all student records and store them in a list.
def fetchAll( self ):
    theRecords = list()
    student = self.fetchRecord()
    while student != None:
        theRecords.append( student )
        student = self.fetchRecord()
    return theRecords

#Extract the next stuent record from the file.
def fetchRecord( self ):
    #Read the first line of the record.
    line = self._inputFile.readline()
    print ( line )
    line = line.split( ',' )
    print ( line )
    if line == "":
        return None

    #If there is another record, create a storage object and fill it
    student = StudentRecord()
    student.idNum = int( line[0] ) 
    student.firstName = line[1]
    student.lastName = line[2]
    student.classCode = int( line[3] )
    student.gpa = float( line[4] )
    return student


class StudentScreenWriter:
    #Prints the student report to screen.
    def printReport( theList ):
         #The class names associated with the class codes.
         classNames = ( None, "Freshman", "Sophomore", "Junior", "Senior" )

        #Print the header.
        print( "LIST OF STUDNETS".center(50) )
        print( "" )
        print( "%-5s %-25s %-10s %-4s" % ('ID', 'NAME', 'CLASS', 'GPA' ) )
        print( "%5s %25s %10s %4s" % ('-' * 5, '-' * 25, '-' * 10, '-' * 4) )

        #Print the body.
        for record in theList:
            print( "%5d %-25s %-10s %4.2f" % (record.idNum, record.lastName + ", " + record.firstName, classNames[record.classCode], record.gpa) )

        #Add a footer.
        print( "-" * 50 )
        print( "Number of students:", len(theList) )

class StudentFileWriter:
    #Prints the student report to file.
    def printReport( theList, out ):
        for record in theList
            record.idNum = str(record.idNum)
            record.lastName = str(record.lastName)
            record.firstName = str(record.firstName)
            record.classCode = str(record.classCode)
            record.gpa = str(record.gpa)

            out.write( record.idNum + ", " + record.lastName + ", " + record.firstName + ", " + record.classCode + ", " + record.gpa )
        out.write( "\n" )


class StudentRecord:
    def __init__( self ):
        self.idNum = None
        self.firstName = None
        self.lastName = None
        self.classCode = None
        self.gpa = None

---

你需要换线

 line = input.split( ', ' )

到

然后移动它

if line == "":
    return None    

---

输入在当前上下文中未定义。
不是您要寻找的答案，但您应该考虑

class StudentRecord:
     def __init__(self,idNum=-1,firstName="unknown",lastName="Unknown",classCode=-1,gpa=-1):
         self.idNum = idNum
         self.firstName = firstName
         self.lastName = lastName
         self.classCode = classCode
         self.gpa = gpa
     #... The rest of your class

使用csv模块

import csv
with open("some.txt") as f:
    reader = csv.reader(f)
    for student_details in reader:
        student = StudentRecord(*student_details)

with open("some.txt") as f:
    for line in f:
        student_details = line.split(",")
        student = StudentRecord(*student_details)

没有csv模块

import csv
with open("some.txt") as f:
    reader = csv.reader(f)
    for student_details in reader:
        student = StudentRecord(*student_details)

with open("some.txt") as f:
    for line in f:
        student_details = line.split(",")
        student = StudentRecord(*student_details)

使用数据进行测试

class StudentRecord:
    def __init__(self,idNum=-1,firstName="unknown",lastName="Unknown",classCode=-1,gpa=-1):
        self.idNum = idNum
        self.firstName = firstName
        self.lastName = lastName
        self.classCode = classCode
        self.gpa = gpa
    def  __str__(self):
        return "#%s:%s, %s | %s = %s"%(
            self.idNum,self.lastName,self.firstName,
            self.classCode,self.gpa
            )
    def __repr__(self):
        return "<Student Record (%s %s)>"%(
            self.firstName,self.lastName
            )

with open("txt_data.txt") as f:
    for line in f:
        student_data = line.strip().split(", ")
        student = StudentRecord(*student_data)
        print "Student:",student

>>> for line in f:  
        li1 = []  
        for part in line.split(','):  
                part = part.strip()  
                li1.append(part)  
        li2.append(li1)  

>>> for i in li2:
        print i
['10015', 'John', 'Smith', '2', '3.01']  
['10208', 'Patrick', 'Green', '1', '3.95']  
['10334', 'Jane', 'Roberts', '4', '3.81']  

你可以考虑把数据拆分（使用你的数据）
li1
和
li2
是列表。而
f
是输入文件，其中每行都有一条记录/数据

现在您将获得列表。您可以使用相同的方法获取和处理名称、类代码、gpa等。
应该是line.split（“，”），我认为逗号后不应该有空格。CSV文件由单个字符严格分隔。我这样说的原因是，分割队列将更安全，尤其是对于丢失的数据。i、 e.
10015，John，Smith，，3.01
@KeyferMathewson:修复后发生了什么？请在拆分前打印行。。然后。。。把你的结果放在原稿上question@JoranBeasley出于某种原因，它甚至没有打印到外壳上。我将发布上面的全部代码。如果您正在重写并建议更好的解决方案，请建议使用
csv
模块解析已编辑的csv文件。。。我想这就是你使用csv阅读器的方式：P。。。在我看来，csv.reader模块一直是一个典型的滥杀滥伤案例；对于这样一个简单的示例，您的代码从一行非常明显的代码（line.split（“，”）更改为一个方法调用，您必须尝试记住forthere:P now everyons的语法happy@sapi我个人认为，学习语法的成本远远超过了它内置的额外功能。例如，如果OP使用的是欧洲编号方案（使用
3,85
而不是
3.85
），则拆分将无法按预期工作（在带有逗号的字段中也无法工作）。