无法比较 python 中的两个字符串

Question

我需要检查是否有函数调用，我知道它不是 txt 文件，但是当我读取一行并尝试使用 type() 打印时，它说 str 并让我打印所有文件正确但出于某种原因无法比较这些行，我不知道为什么，当我编译时没有显示错误，文件的第一行是 '#include <Arduino.h>' 并且找到的 var 无论如何都是 false

import os
def BeforeBuild():
    found = False
    with open(r"\src\OTAWEBAP.cpp", "r") as f:
        for line in f:
            print (line)
            if(line == '#include <Arduino.h>'):
                found = True;
        if(not found):
            raise Exception("OtaIni function not found, you need to use it to preserve OTA functions in your new deploy")
        else:
            print('function OtaIni was found')
    f.close()
BeforeBuild()

Answer 1

换行的话最后一个字符是\n

所以这可能对你有用：-

import os
def BeforeBuild():
    found = False
    with open(r"\src\OTAWEBAP.cpp", "r") as f:
        for line in f:
            print (line)
            if(line[:-1] == '#include <Arduino.h>'):
                found = True;
        if(not found):
            raise Exception("OtaIni function not found, you need to use it to preserve OTA functions in your new deploy")
        else:
            print('function OtaIni was found')
    f.close()
BeforeBuild()

Answer 2

尝试替换

if(line == '#include <Arduino.h>'):
            found = True;

和

if line.strip() == '#include <Arduino.h>':
    found = True

strip() 函数删除行首和行尾的所有空格。

P. S. 尽量记住在 Python 中，if 条件不需要在括号中并且行末尾不需要分号。否则大家都会知道你本质上是一个C程序员。

Answer 3

比较字符串时要小心。在这种情况下，一个 whitespace 字符导致了这个问题。有很多 whitespace 字符看不到但可能会出现。因此，在处理此类文件时，一个好的做法是删除这些 whitespace 字符。您可以使用 strip() 从字符串的两端删除 whitespace 个字符。

import os
def BeforeBuild():
    found = False
    with open(r"\src\OTAWEBAP.cpp", "r") as f:
        for line in f:
            line = line.strip();
            print (line)
            if line == '#include <Arduino.h>':
                found = True;
        if not found:
            raise Exception("OtaIni function not found, you need to use it to preserve OTA functions in your new deploy")
        else:
            print('function OtaIni was found')
    f.close()
BeforeBuild()

无法比较 python 中的两个字符串

Can´t compare two strings in python

python

string

text-files