c - C中\n字符的诅咒

Question

我制作了一个简单的拼写检查程序，它读取字典和用户文本文件以进行检查。该程序需要显示任何不在词典中的单词的行和单词索引。因此它可以正常工作，直到用户文本文件中有返回 \n 字符(在段落或句子的末尾)。所以 Hello 实际上是针对字典作为 Hello\n 进行测试的，程序认为它的拼写错误。谁能建议一种删除 \n 字符的方法？这是我的代码:

#include <stdio.h>
#include <string.h>

void StrLower(char str[])
{
    int i;

    for (i = 0; str[i] != '\0'; i++)
        str[i] = (char)tolower(str[i]);
    }

int main (int argc, const char * argv[]) {
    FILE *fpDict, *fpWords;

    fpWords = fopen(argv[2], "r");
    if((fpDict = fopen(argv[1], "r")) == NULL) {
        printf("No dictionary file\n");
        return 1;
    }

    char dictionaryWord[50]; // current word read from dictionary
    char line[100]; // line read from spell check file (max 50 chars)
    int isWordfound = 0; // 1 if word found in dictionary
    int lineCount = 0; // line in spellcheck file we are currently on
    int wordCount = 0; // word on line of spellcheck file we are currently on

    while ( fgets ( line, sizeof line, fpWords ) != NULL )
    { 
        lineCount ++;
        wordCount = 0;
        char *spellCheckWord;
        spellCheckWord = strtok(line, " ");
        while (spellCheckWord != NULL) {
            wordCount++;
            spellCheckWord = strtok(NULL, " ,");

            if(spellCheckWord==NULL)
                continue;

            StrLower(spellCheckWord);
            printf("'%s'\n", spellCheckWord);


            while(!feof(fpDict))
            { 
                fscanf(fpDict,"%s",dictionaryWord);
                int res = strcmp(dictionaryWord, spellCheckWord);

                if(res==0)
                {
                    isWordfound = 1;
                    break;
                }
            }

            if(!isWordfound){
                printf("word '%s' not found in Dictionary on line: %d, word index: %d\n", spellCheckWord, lineCount, wordCount); //print word and line not in dictionary
            }


            rewind(fpDict); //resets dictionarry file pointer 
            isWordfound = 0; //resets wordfound for next iteration

        }
    }

    fclose(fpDict);
    fclose(fpWords);
    return 0;
}

哇，感谢大家的快速回复。你们太棒了，太棒了!

Answer 1

在 fgets() 调用后立即删除 '\n':

while ( fgets ( line, sizeof line, fpWords ) != NULL )
{
    size_t linelen = strlen(line);
    assert((linelen > 0) && "this can happen only when file is binary");
    if (line[linelen - 1] == '\n') line[--linelen] = 0; /* remove trailing '\n' and update linelen */