Question

示例：

三个文件

hi.txt

在txt中：“我们可以成为”

again.txt

txt内部：“曾经”

的人

final.txt

txt内部：“知道C”

然后，另一个名为“订单”的文件

将Order.txt

在txt中：

“的 hi.txt; 6 ”

“的 again.txt; 7 ”

“的 final.txt; 3 ”

我想要的：读取第一个文件名，打开它，列出内容，等待6秒，读取第二个名称，打开它，列出内容，等待7秒，读取第三个名称，打开它，列出内容，等待3秒。

如果我这样做而没有打开内容（你会在我的代码上看到第二个）并列出名称，它可以正常工作，但由于某种原因，它不是关于内容的。

orderFile = fopen("order.txt","r");

    while(fscanf(orderFile,"%49[^;];%d",fileName,&seconds) == 2)
    {
        contentFile = fopen(fileName,"r");

        while(fscanf(contentFile,"%[^\t]",textContent) == 1)
        {
            printf("%s\n", textContent);
        }

        sleep(seconds);

        fclose(contentFile);
    }

fclose(orderFile);

输出：

我们可以

（等待7秒）

程序以“RUN SUCCESSFUL”结束

EDIT @

现在，正如你们所说，这就是问题所在：

旧

while(fscanf(orderFile,"%49[^;];%d",fileName,&seconds) == 2)

新

while(fscanf(orderFile," %49[^;];%d",fileName,&seconds) == 2)

我有一个“艰难”的时间来完全理解它，空间有什么作用？不接受进入？空间？究竟是什么？

Answer 1

不要使用fscanf

int
main()
{
    FILE *orderFile = fopen("order.txt", "r");
    if (orderFile != NULL)
    {
        int  seconds;
        char line[128];

        /* 
         * fgets, read sizeof line characters or unitl '\n' is encountered
         * this will read one line if it has less than sizeof line characters
         */
        while (fgets(line, sizeof line, orderFile) != NULL)
        {
            /* 
             * size_t is usually unsigned long int, and is a type used 
             * by some standard functions.
             */
            size_t fileSize;
            char  *fileContent;
            FILE  *contentFile;     
            char   fileName[50];
            /* parse the readline with scanf, extract fileName and seconds */
            if (sscanf(line, "%49[^;];%d", fileName, &seconds) != 2)
                continue;
            /* try opening the file */
            contentFile = fopen(fileName,"r");
            if (contentFile == NULL)
                continue;
            /* seek to the end of the file */
            fseek(contentFile, 0, SEEK_END);
            /* 
             * get current position in the stream, 
             * it's the file size, since we are at the end of it 
             */
            fileSize = ftell(contentFile);
            /* seek back to the begining of the stream */
            rewind(contentFile);
            /* 
             * request space in memory to store the file's content
             * if the file turns out to be too large, this call will
             * fail, and you will need a different approach.
             * 
             * Like reading smaller portions of the file in a loop.
             */
            fileContent = malloc(1 + fileSize);
            /* check if the system gave us space */
            if (fileContent != NULL)
            {
                size_t readSize;
                /* read the whole content from the file */
                readSize = fread(fileContent, 1, fileSize, contentFile);
                /* add a null terminator to the string */
                fileContent[readSize] = '\0';
                /* show the contents */
                printf("%s\n", fileContent);
                /* release the memory back to the system */
                free(fileContent);
            }
            sleep(seconds);
            fclose(contentFile);
        }
        fclose(orderFile);  
    }

    return 0;
}

代码中几乎没有解释所有内容，如果您需要更多信息，请阅读手册。

从C中的多个文件中读取内容

1 个答案: