python中两个文件的合并

本文将会分析一个文件合并的程序，并指出在合并文件过程中需要注意的问题。

下面是需要合并的文件示例：





分析思路：

要将两个文件合并，首先要将文件读到内存中，成为列表。再将列表分割，按照类别将数据分开存储，即姓名、电话、邮箱。通过遍历列表1，依次与列表2比较，如果二者有重合的人，那么直接利用 .join([ ])姓名电话邮箱合并到一行，保存到另外一个列表变量里面。二者不重合的人，说明只有列表1中才有，故将此人的邮箱信息用str(‘—–’)代替。

经过这次遍历之后，列表1中所有的人和列表2中与列表1中重复的人，都重新整合到了新的列表变量里面。接下来还需要把列表2中特有的人，添加到新的列表变量中。方法是遍历列表2，把与列表1不重合的人取出来保存。

最后要将新的列表变量中的数据写入到新的文件中，并关闭所有文件。

流程图如下：



代码如下：

"""
Created on Fri Aug  4 12:59:36 2017

@author: 13323
"""
# This program can combine two or more files into one file.
def main():
#firstly open the files
data1 = open("test_3.txt","rb")
data2 = open("test_4.txt","rb")

# read the data in file into list
data1.readline() #only read one line, skip the first line
data2.readline() #only read one line, skip the first line
file1 = data1.readlines() #read all variable into list file1
file2 = data2.readlines() #read all variable into list file2
#print(file1)

#define particular list to store variable
file1_name = []
file1_tel = []
file2_name = []
file2_email = []
#file3 = []

#split file1 into two part
for line in file1:
element = line.split() #line.split(); devide by ' '
file1_name.append(str(element[0].decode('gbk')))
file1_tel.append(str(element[1].decode('gbk')))

#split file2 into two part
for line in file2:
element = line.split()
file2_name.append(str(element[0].decode('gbk')))
file2_email.append(str(element[1].decode('gbk')))

# pick up the name in the file1 same as the name in the file2 and combine
file3 = []
for i in range(len(file1_name)):
s = ''
if file1_name[i] in file2_name:
j = file2_name.index(file1_name[i])
s = '\t'.join([file1_name[i],file1_tel[i],file2_email[j]])
s += '\n'
else:
s = '\t'.join([file1_name[i],file1_tel[i],str("----")])
s += '\n'
file3.append(s)

#pick up the name in the file1 doesn't same as the name in the file2
for i in range(len(file2_name)):
s = ''
if file2_name[i] not in file1_name:
s = '\t'.join([file2_name[i],str('----'),file2_email[i]])
s += '\n'
file3.append(s)

#write the data into file3
data3 = open("test_5.txt","w")
data3.writelines(file3)

#close the file
data1.close()
data2.close()
data3.close()

main()

关键点：

编码与解码

列表合并与拆解