如何修改TXT遍历代码适配组名前置格式并修复尾行问题

Let's sort out this parser step by step. Your original code had two main issues: it relied on a trailing blank line to save the last group, and it was built for group names coming after the data lines instead of before. Here's a revised solution that addresses both problems, plus cleaner line handling.

First, Let's Clarify the New Input Format #

Since you need group names to come before their associated data lines, your input should look like this (adjusted from your example):

1
grupa12
239.0.1.122,kanal6
239.0.1.116,kanal7
1.5,kanal8
4.5,kanal9
grupa123
239.0.1.119,kanal10
239.0.1.112,kanal11
4.5,KANAL112
4.0,KANAL123
1.5,KANAL134
grupa1234

Revised Code #

from itertools import islice

def parse_mcast_data(file_path):
    MCAST_GROUPS = []
    current_group = None
    current_addresses = []
    current_values = []
    current_names = []
    
    with open(file_path, "r") as filestream:
        # Read the first line as scanTime
        first_line = next(islice(filestream, 0, 1)).strip()
        scanTime = int(first_line)
        
        for line in filestream:
            line = line.strip()
            if not line:  # Skip blank lines entirely
                continue
            
            if line.startswith("grupa"):
                # Save the previous group if we have one
                if current_group is not None:
                    MCAST_GROUPS.append([
                        current_group,
                        current_addresses.copy(),
                        current_values.copy(),
                        current_names.copy()
                    ])
                # Start a new group
                current_group = line
                current_addresses = []
                current_values = []
                current_names = []
            else:
                # Split data line into parts (handle cases where comma might have spaces?)
                parts = line.split(",")
                if len(parts) != 2:
                    continue  # Skip malformed lines
                
                value_or_addr, name = parts
                name = name.strip()
                
                # Check if it's an IP address (>=2 dots) or a numeric value (<=1 dot)
                dot_count = value_or_addr.count(".")
                if dot_count >= 2:
                    current_addresses.append(value_or_addr.strip())
                else:
                    # Try to convert to float (handles integers like "1" too)
                    try:
                        num_val = float(value_or_addr.strip())
                        current_values.append(num_val)
                    except ValueError:
                        # If it's neither IP nor numeric, skip or log?
                        continue
                current_names.append(name)
        
        # Save the last group after loop ends (no trailing blank line needed!)
        if current_group is not None:
            MCAST_GROUPS.append([
                current_group,
                current_addresses,
                current_values,
                current_names
            ])
    
    return MCAST_GROUPS, scanTime

# Example usage
groups, scan_time = parse_mcast_data("INPUT_DATA_SIMULATION.txt")
print(f"Scan Time: {scan_time}")
for group in groups:
    print(f"\nGroup: {group[0]}")
    print(f"Addresses: {group[1]}")
    print(f"Values: {group[2]}")
    print(f"Names: {group[3]}")

Key Improvements Explained #

• Reverse Format Support: We now detect grupa lines first, start a new group, then collect all subsequent data lines until the next grupa line.
• No Trailing Blank Line Required: After the loop finishes, we check if there's an unsaved group and add it—this fixes the original issue where the last group wouldn't save without a blank line.
• Cleaner Line Handling: Using strip() removes leading/trailing whitespace (including \n) from every line, so we don't have to manually slice [:-1] or check for \n in strings. Blank lines are skipped entirely.
• Robust Data Classification: Instead of counting dots manually with a loop, we use count(".") for simplicity. We also add a try/except block to safely convert numeric values, which handles edge cases like integers (e.g., "1" instead of "1.0").
• Avoids Global Variables: All group-related lists are initialized inside the function and scoped properly, preventing unexpected state leaks between function calls.
• Malformed Line Handling: The code skips lines that don't split into exactly two parts, making it more resilient to bad input.

内容的提问来源于stack exchange，提问作者kaszankabanka