Python：通过名称在字符串中访问结构字段(Python: access structure field through its name in a string)

Python：通过名称在字符串中访问结构字段(Python: access structure field through its name in a string)

在Scapy中，我想比较任意两个数据包a和b之间的多个头字段。 这个字段列表是预定义的，例如：

fieldsToCompare = ['tos', 'id', 'len', 'proto'] #IP header

通常我会单独做：

if a[IP].tos == b[IP].tos: ... do stuff...

有没有办法从字符串列表中访问这些数据包字段，包括每个字符串被称为什么？ 喜欢：

for field in fieldsToCompare: if a[IP].field == b[IP].field: ... do stuff...

In Scapy, I want to compare a number of header fields between any two packets a and b. This list of fields is predefined, say:

fieldsToCompare = ['tos', 'id', 'len', 'proto'] #IP header

Normally I would do it individually:

if a[IP].tos == b[IP].tos: ... do stuff...

Is there any way to access those packet fields from a list of strings including what each one of them is called? Like:

for field in fieldsToCompare: if a[IP].field == b[IP].field: ... do stuff...

最满意答案

你可以使用getattr() 。 这些线是相同的：

getattr(x, 'foobar') x.foobar

setattr()是它的对手。

You can use getattr(). These lines are equivalent:

getattr(x, 'foobar') x.foobar

setattr() is its counterpart.