Python 3.5.2中write函数使用及精准查找文件问题求助

Let's break down the issues in your code and fix them step by step:

Key Issues in Your Current Code #

• Incorrect open() parameters: You're concatenating the mode string (w) to the filename, which creates invalid filenames like test.txtw. The open() function expects the filename and mode as separate arguments.
• Wrong equality check: In Python, = is for assignment, not comparison. Use == to check if mode equals "w".
• Calling write() on the wrong object: You tried to call write() on the fileName string variable, but only the file object returned by open() has this method.
• Unnecessary semicolons: Python doesn't require semicolons at the end of lines (they're allowed but not standard practice).

Corrected Basic Version #

This fixes the core issues and ensures you target the right file:

fileName = input("What file do you want to target?(add file type i.e. .exe,.html,.txt)")
print("Opening the file...")
mode = input("w,r,r+ or a?")
if mode == "w":
    # Pass filename and mode as separate arguments to open()
    writeToFile = open(fileName, mode)
    # Use the file object to call write()
    writeToFile.write("sample text")
    # Always close the file when done to free resources
    writeToFile.close()

Recommended Version (Using with Statement) #

For better resource management, use Python's with statement—it automatically closes the file when you're done, even if an error occurs:

fileName = input("What file do you want to target?(add file type i.e. .exe,.html,.txt)")
print("Opening the file...")
mode = input("w,r,r+ or a?")
if mode == "w":
    # The with block handles file closing automatically
    with open(fileName, mode) as writeToFile:
        writeToFile.write("sample text")

Quick Notes for Python 3.5.2 #

• The "w" mode will create the file if it doesn't exist, or overwrite its contents if it does. Use "a" if you want to append to an existing file instead.
• Always make sure the file path is correct—if the file isn't in your script's working directory, you'll need to provide the full path (e.g., C:/Documents/test.txt on Windows or /home/user/test.txt on Linux/macOS).

内容的提问来源于stack exchange，提问作者Will