小编epi*_*ras的帖子

Import React VS Import React, { Component }

哪一个更好,为什么？

或者除了稍后编写更少的代码之外它没有任何区别？

写作是否{ Component }意味着它只导入Component对象？

我正在研究pset4对Harvard的cs50x的恢复,因为open保持返回NULL而被卡住了.

// Read each 512 bytes until end of file is reached
FILE* img = NULL;

while (fread(&data, 512, 1, diskptr) == 1)
{
    // Check for jpeg start
    if (checkStart(data, jStart, jStartOE) == true)
    {
        jFound++;
        if (jFound == 1)
        {
            printf("newfound\n");
            // Name and open the first jpeg file
            char title[12];
            sprintf(title, "%03d.jpg", jFound - 1);
            FILE* img = fopen(title, "w");
            fwrite(&data, 512, 1, img);
        }
        else if (img != NULL)
        {
            printf("closed\n");
            // Close old file
            fclose(img); …