Python讀寫文件

File Handling的Python File Write¹

Write to an Existing File To write to an existing file, you must add a parameter to the open() function:

“a” - Append - will append to the end of the file “w” - Write - will
overwrite any existing content

Create a New File To create a new file in Python, use the open()
method, with one of the following parameters:

“x” - Create - will create a file, returns an error if the file exist
“a” - Append - will create a file if the specified file does not exist
“w” - Write - will create a file if the specified file does not exist

通過Open讀寫（最簡單的讀寫方式）

f= open("file/bigData.csv","r")
f_reader = csv.reader(f)

for item in f_reader :
    if f_reader.line_num == 1:
big_file_open.close()

#a+，打開文件並添加數據，如果文件不存在，則創建
f = open("file/bigData.csv", "a+")

#指定編碼格式
f = open(sql_template_file,"r",encoding='utf-8')

#通過enumerate讀取文件，可以記錄行號i
for i,line in enumerate(f.splitlines()):

通過With open讀寫

 with open("file/bigData.csv") as f:
 	#line 讀取指定行
 	item1 = f.readlines()[line].split(",")[0]
 	#讀取 10 到 100 行區間數據
 	data = f.readlines()[10:100]
 f.close()

返回文件頭，繼續讀取

#while循环结束后，指针到文件末尾
inputFile.seek(0) #返回文件头
line=inputFile.readline() #再次初始化，指向文件头

循環緩存數據

    f_mt = open(file_mt, "r")
    f_mt_data = f_mt.read()
    
    for line_mt in f_mt_data.splitlines():
        start_time_mt = line_mt.split(",")[0]
     或者
     for line in f_mt_data.split('\n'):