如何将CSV文件中的15位IMEI号格式化为指定带空格形式？

Looks like you're halfway there! Let's finish up that code to reformat those IMEIs into the "XX XXXXXX XXXXXX X" format you need. Here's a complete, robust solution:

Complete Code Solution #

import csv

def reformat_imei(imei):
    # Convert to string and clean up any extra whitespace
    imei_str = str(imei).strip()
    
    # Validate it's a 15-digit number before formatting
    if len(imei_str) != 15 or not imei_str.isdigit():
        # Return original if invalid (adjust to raise error if preferred)
        return imei_str
    
    # Slice the string into the required segments and format with spaces
    return f"{imei_str[:2]} {imei_str[2:8]} {imei_str[8:14]} {imei_str[14]}"

# Get input file name from user
file_csv = input("Enter file name: \n")
output_file = f"formatted_{file_csv}"

# Read original CSV and write formatted data to a new file
with open(file_csv, "r", newline='') as infile, open(output_file, "w", newline='') as outfile:
    # Use DictReader if your CSV has headers (easier to reference columns by name)
    reader = csv.DictReader(infile)
    writer = csv.DictWriter(outfile, fieldnames=reader.fieldnames)
    
    # Write the header row first
    writer.writeheader()
    
    # Process each row
    for row in reader:
        # Replace 'IMEI' with your actual column name (e.g., 'IMEI_Number')
        imei_column_name = 'IMEI'
        row[imei_column_name] = reformat_imei(row[imei_column_name])
        writer.writerow(row)

print(f"Success! Formatted CSV saved as {output_file}")

Key Details Explained #

1. The IMEI Reformatting Function #

The reformat_imei function handles all the heavy lifting:

• Converts the input to a string (in case your CSV stores IMEIs as numbers) and strips any extra spaces.
• Validates that the IMEI is exactly 15 digits (skips formatting if it's invalid, so you don't get broken strings).
• Uses string slicing to split the 15-digit string into the required parts:
  • imei_str[:2]: First 2 characters
  • imei_str[2:8]: Next 6 characters (indices 2 to 7 inclusive)
  • imei_str[8:14]: Next 6 characters (indices 8 to 13 inclusive)
  • imei_str[14]: Last 1 character (index 14, since Python uses 0-based indexing)

2. CSV Handling #

• We use csv.DictReader and csv.DictWriter because they let you reference columns by name (like row['IMEI']) instead of indices, which is more readable and less error-prone.
• We write to a new file (formatted_yourfile.csv) instead of overwriting the original, so you don't lose your raw data.

3. If Your CSV Doesn't Have Headers #

If your CSV doesn't use column headers, switch to csv.reader and use column indices instead:

# Alternative code for CSV without headers
with open(file_csv, "r", newline='') as infile, open(output_file, "w", newline='') as outfile:
    reader = csv.reader(infile)
    writer = csv.writer(outfile)
    
    # Skip this line if there's no header row
    writer.writerow(next(reader))
    
    for row in reader:
        # Assuming IMEI is in the second column (index 1; change to match your CSV)
        imei_column_index = 1
        row[imei_column_index] = reformat_imei(row[imei_column_index])
        writer.writerow(row)

Edge Cases to Consider #

• If some entries in your CSV aren't 15-digit IMEIs, the function will leave them as-is. You can modify the validation step to raise an error or flag invalid entries if needed.
• Make sure your CSV uses standard formatting (comma-separated values). If it uses a different delimiter (like tabs), add delimiter='\t' to the csv.reader/csv.DictReader calls.

内容的提问来源于stack exchange，提问作者Vvega