第四十四条。一次打印一行。增加行时出现问题

Question

我正在尝试编写一个脚本，可以一次提取一行excel并打印出来。我想使用一种方法来更改行。我可以得到要更改的行的值（变量rrowx），但是当我打印currentRow字符串时，我得到的是原始行，而不是新调整的行。你知道吗

import xlrd
class Loader(object): ## engine to load and unload spread sheets 
                      ## then sets them to a variable
     # set the variables
     workbook = " "      # name of the file
     sheetCount = 0      # amount of sheets in the spreadsheet
     sheetNumber = 0     # current sheet (index)
     rowCount = 0        # amount of rows in the spreadsheet
     currentSheet = " "  # name of current sheet
     topRow = " "        # row 0 string
     currentRow = " "    # row x string
     global rrowx
     rrowx = 0

     # begin the load  
     workbook = xlrd.open_workbook('test.xlsx')
     sheetCount = workbook.nsheets
     sheetNames = workbook.sheet_names()
     currentSheet = workbook.sheet_by_index(sheetNumber)
     #topRow = currentSheet.row_values(rowx=rrowx, start_colx=scolx, end_colx=ecolx)
     currentRow = currentSheet.row_values(rowx=rrowx)

    #  methods to navigate the sheet 
     def nextrow(self):
        global rrowx
        print(rrowx)
        rrowx += 1 
        print(rrowx)
        return rrowx

spreadsheet = Loader()
## Debuggin prints
print(spreadsheet.sheetNames)
print(spreadsheet.sheetCount)
print("What Sheet would you like to use? (Use numbers)")
spreadsheetadjust = int(input())                   # takes input as a interger
spreadsheet.currentSheet = spreadsheetadjust - 1   # takes input and -1 for index value
print ('Current sheet name: %s' % spreadsheet.currentSheet)# prints current sheet name
print('top row:')
#print(spreadsheet.topRow)
print('row 1 ')
print(spreadsheet.currentRow)
print("NextRow")
spreadsheet.nextrow()
print(spreadsheet.currentRow)

我想在更改了rowx变量并再次调用currentRow上的print之后，将更改打印的行。但是我得到的是两次打印同一行，尽管我可以看到rorowx的值随着我在方法中添加的打印而改变。你知道吗

披露：我只做了一个月的编程，所以很抱歉，如果这是一个简单的答案，我只是错过了。你知道吗

Answer 1

我强烈建议您阅读python面向对象基础知识。您的代码有多个问题，我将提到一些：

• 您的类变量是类变量，意味着 类将共享相同的变量。所以如果你创造了多个 在类的实例中，您将获得意外/不希望的行为。

• 不建议使用global变量，尤其是在 我可以不用它。

• 您不需要在python中初始化变量

• 在您的实现中 spreadsheet.currentSheet = spreadsheetadjust - 1即使修复了，也会导致失败 你的问题。你想要什么 spreadsheet.sheetNumber = spreadsheetadjust - 1

下面是正确使用python类的代码：

import xlrd


class Loader:
    def __init__(self, path_to_xlsx='test.xlsx'):
        self.sheetNumber = 0
        self.rrowx = 0
        self.workbook = xlrd.open_workbook(path_to_xlsx)
        self.sheetCount = self.workbook.nsheets
        self.sheetNames = self.workbook.sheet_names()
        self.currentSheet = self.workbook.sheet_by_index(self.sheetNumber)
        self.currentRow = self.currentSheet.row_values(rowx=self.rrowx)

    def nextrow(self):
        self.rrowx += 1
        self.currentRow = self.currentSheet.row_values(rowx=self.rrowx)


spreadsheet = Loader()

print("What Sheet would you like to use? (Use numbers)")
spreadsheetadjust = int(input())  # takes input as a interger
spreadsheet.sheetNumber = spreadsheetadjust - 1  # takes input and -1 for index value

print('Current sheet name: %s' % spreadsheet.currentSheet)  # prints current sheet name
print(spreadsheet.currentRow)

spreadsheet.nextrow()
print(spreadsheet.currentRow)