如何用Python提取文件中两个偏移量之间的十六进制值

Hey there! Let's figure out how to pull those hex values from your target offset range. Since you already have the interval (like 117:126) mapped out, here are practical, easy-to-follow approaches depending on what you're working with:

If you're using Python, this is a straightforward way to extract the exact hex values you need:

• First, open your file in binary mode—critical for handling raw byte data instead of text.
• Calculate the number of bytes to read: if your range is start:end, that's end - start + 1 bytes (assuming both offsets are inclusive).
• Jump to the starting offset, read the target bytes, then convert them to a hex string.

Here's a ready-to-use function:

def extract_hex_from_range(file_path, start_offset, end_offset):
    # Calculate total bytes to fetch (adjust if your end offset is exclusive)
    byte_count = end_offset - start_offset + 1
    
    with open(file_path, 'rb') as file:
        # Move the file pointer to the starting offset
        file.seek(start_offset)
        # Read the exact number of bytes in the range
        target_bytes = file.read(byte_count)
        # Convert bytes to a clean hex string (use .lower() for lowercase)
        hex_result = target_bytes.hex().upper()
    
    return hex_result

# Example usage: for offset range 117:126
hex_values = extract_hex_from_range("your_target_file.bin", 117, 126)
print(f"Hex values in range 117:126: {hex_values}")

Quick Notes: #

• Double-check if your offsets are zero-indexed or one-indexed. If your tool outputs one-indexed values, subtract 1 from both start and end to match Python's zero-based system.
• The hex() method turns each byte into two hex characters, so a 10-byte range will become a 20-character hex string.

If you'd rather skip writing a script, these built-in tools work like a charm:

Linux/macOS: Use xxd #

xxd is a go-to for hex dumping files. To extract your range:

# Syntax: xxd -s <start_offset> -l <number_of_bytes> <file_path>
# For range 117:126, we need 10 bytes (126-117+1)
xxd -s 117 -l 10 your_target_file.bin

This shows offsets, hex values, and ASCII. To get just the raw hex string (no spaces or newlines):

xxd -s 117 -l 10 your_target_file.bin | cut -c 10-50 | tr -d ' \n'

Windows: Use certutil or PowerShell #

With certutil: #

# First dump the file to a hex text file
certutil -encodehex your_target_file.bin temp_hex.txt
# Manually extract the lines matching your offset range (each line covers 16 bytes by default)

With PowerShell (Precise Extraction): #

Get-Content your_target_file.bin -Raw | 
    ForEach-Object { $_.ToCharArray() | Select-Object -Skip 117 -First 10 } | 
    ForEach-Object { [System.BitConverter]::ToString([byte[]]$_) } | 
    ForEach-Object { $_ -replace '-', '' }

At the end of the day, all these methods boil down to the same core steps: jump to the starting byte, read exactly the bytes in your range, then convert those bytes to their hexadecimal form.

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