Question

所以我有一个作为读取文件打开的输入文件，它是一个疯狂的lib，也是一个将mad-lib复制到输出（写入）文件的函数。输入文件中的一个例句是＆＃34;我姐姐是一个非常＆lt;形容词＆gt;人＆＃34。令牌单词是＆＃34;＆lt;＆gt;＆＃34;中的单词。那么，如果单词是一个标记，我将如何创建一个返回true的布尔函数？我可以使用fscanf吗？

FILE* open_file(char prompt[], char mode[]);
bool istoken(char word[]);
void process_file(FILE* in, FILE* out);


int main(int argc, const char * argv[]) {
    FILE* in = NULL;
    FILE* out = NULL;

    printf("MAD-LIBS Text Processor\n");
    printf("The Program will open a mad-libs file, ask you to fill various words, and produce a funny story.\n");

    in = open_file("Enter mad-lib file name:\n", "r");
    out = open_file("Enter file name for resulting story:\n", "w");
    process_file(in, out);

    fclose(in);
    fclose(out);
    return 0;
}

/* open_file = prompts user for file name & and attempts to open it, if it fails it prompts the user again. */
FILE* open_file(char prompt [], char mode[]) {
    char filename[255];
    FILE* in;

    do {
        printf("%s", prompt);
        scanf("%s", filename);

        in = fopen(filename, mode);

        if (in == NULL) {
            printf("Unable to open file: %s. Try Again!\n", filename);
        }
    } while(in == NULL);
    return in;
}
/* process_file = processes entire input file and writes it to output file */
void process_file(FILE* in, FILE* out) {
    char content[MAX_LEN];

    while(fgets(content, MAX_LEN, in) != NULL) {
        fprintf(out, "%s", content);
    }
}
/* istoken = returns true if word is a token */
bool istoken(char word[]) {                 //USE FSCANF MAYBE
    char target = '<';



    return true;
}

Answer 1

回答你提出的问题：

#include <string.h>

...

bool istoken(char word[])
{
  return (word[0]=='<' && word[strlen(word)-1]=='>');
}

当然这完全取决于传入正确的NUL终止字符串。如果您将指针传递到缓冲区中间的某个位置：

bool istoken(char word[], size_t wordLength)
{
  return (word[0]=='<' && word[wordLength-1]=='>')
}

然而，在调用这些函数之前，你需要做一些单词解析工作。

如果一个单词是所谓的＆＃34;令牌＆＃34;如何返回true

1 个答案: