如何用Python在in.txt中查找指定number值并验证info字段条件？

我有一个文件in.txt，内容如下：

name="XYZ_PP_0" number="0x12" bytesize="4" info="0x0000001A"
name="GK_LMP_2_0" number="0xA5" bytesize="8" info="0x00000000bbae321f"
name="MP_LKO_1_0" number="0x356" bytesize="4" info="0x00000234"
name="PNP_VXU_1_2_0" number="0x48A" bytesize="8" info="0x00000000a18c3ba3"
name="AVU_W_2_3_1" number="0x867" bytesize="1" info="0x0b"

需要完成两个任务：

• 查找number="0x867"的行，验证其info值是否等于预期的0x0a，匹配则输出matches，否则输出doesn't matches；
• 查找number="0x12"的行并存储其info值，查找number="0x356"的行存储其info值，验证后者是否等于前者加0x00000004（即0x0000001A + 0x00000004 = 0x0000001E），匹配则输出number="0x12" info value 0x0000001A + 0x00000004 matches to info value of number="0x356".，否则输出resulted value not matching。

我当前的Python尝试代码如下：

with open("in.txt", "r") as infile:

     XYZ = False
     MP = False
     AVU = False
 
     xyz = ['number="0x12"', 'info="0x0000001A"']
     mp  = ['number="0x356"', 'info="0x00000234"']
     avu = ['number="0x867"', 'info="0x0b"']

     for line in infile:
         if all(x in line for x in xyz):
            XYZ = True
            continue

         if all(x in line for x in mp):
            MP = True
            continue
 
         if all(x in line for x in avu):
            AVU = True
            continue  

但该代码仅能检查对应行是否存在，无法实现上述条件验证。请问如何实现查找指定number值并存储对应info值以完成所需条件验证？

核心思路是解析每行的键值对，提取number和info的数值后再做验证，具体实现步骤如下：

1. 编写行解析函数 #

把每行的key="value"格式转换成字典，方便快速提取目标字段：

def parse_line(line):
    parts = line.strip().split()
    data = {}
    for part in parts:
        key, value = part.split('=', 1)
        data[key] = value.strip('"')
    return data

2. 遍历文件收集目标数据 #

初始化变量存储需要的info值，遍历文件时匹配指定number并记录对应info的十进制数值（方便后续计算）：

info_0x12 = None
info_0x356 = None
info_0x867 = None

with open("in.txt", "r") as infile:
    for line in infile:
        line = line.strip()
        if not line:
            continue  # 跳过空行
        data = parse_line(line)
        if data['number'] == '0x12':
            info_0x12 = int(data['info'], 16)
        elif data['number'] == '0x356':
            info_0x356 = int(data['info'], 16)
        elif data['number'] == '0x867':
            info_0x867 = int(data['info'], 16)

3. 执行两个验证任务 #

任务1：验证0x867的info值 #

expected_0x867 = 0x0a
print("matches" if info_0x867 == expected_0x867 else "doesn't matches")

任务2：验证0x356的info是否等于0x12的info加0x4 #

if info_0x12 is not None and info_0x356 is not None:
    expected_0x356 = info_0x12 + 0x4
    if info_0x356 == expected_0x356:
        # 把十进制转回8位十六进制字符串，保持和原文件格式一致
        print(f'number="0x12" info value 0x{info_0x12:08X} + 0x00000004 matches to info value of number="0x356".')
    else:
        print("resulted value not matching")
else:
    print("Missing required lines (0x12 or 0x356)")

完整代码 #

整合所有部分后的完整代码：

def parse_line(line):
    parts = line.strip().split()
    data = {}
    for part in parts:
        key, value = part.split('=', 1)
        data[key] = value.strip('"')
    return data

info_0x12 = None
info_0x356 = None
info_0x867 = None

with open("in.txt", "r") as infile:
    for line in infile:
        line = line.strip()
        if not line:
            continue
        data = parse_line(line)
        if data['number'] == '0x12':
            info_0x12 = int(data['info'], 16)
        elif data['number'] == '0x356':
            info_0x356 = int(data['info'], 16)
        elif data['number'] == '0x867':
            info_0x867 = int(data['info'], 16)

# 执行任务1
expected_0x867 = 0x0a
print("matches" if info_0x867 == expected_0x867 else "doesn't matches")

# 执行任务2
if info_0x12 is not None and info_0x356 is not None:
    expected_0x356 = info_0x12 + 0x4
    if info_0x356 == expected_0x356:
        print(f'number="0x12" info value 0x{info_0x12:08X} + 0x00000004 matches to info value of number="0x356".')
    else:
        print("resulted value not matching")
else:
    print("Missing required lines (0x12 or 0x356)")

代码说明 #

• parse_line函数将每行字符串转为字典，简化字段提取操作；
• 把info值转为十进制整数，是为了方便进行加法运算；
• 输出时用0x{info_0x12:08X}将整数转回8位大写十六进制字符串，和原文件格式保持一致；
• 增加了缺失行判断，避免出现None值运算报错。

内容的提问来源于stack exchange，提问作者V_S