c - strtok 中的可变长度

Question

我看过一些示例并尝试做一些事情，但现在我被卡住了。

工作代码是

    char quality[5][10];
    char * qualities;
    qualities = strtok (message, "\n");
    int k = 0;
    while (qualities != NULL){
        if (k == 0) {
            strcpy(quality[0], qualities);
        }
        else if ( k == 1) {
            strcpy(quality[1], qualities);
        }
        else if ( k == 2) {
            strcpy(quality[2], qualities);
        }
        else if ( k == 3) {
            strcpy(quality[3], qualities);
        }
        else if ( k == 4) {
            strcpy(quality[4], qualities);
        }           
        qualities = strtok (NULL, "\n");
        k++;
    }

然而，这适用于固定长度(在本例中仅为 5)，但是我想将一个变量分配给质量变量，但在那种情况下 while 循环将不起作用。我该怎么办？

Answer 1

替换这个 block

if (k == 0) {
        strcpy(quality[0], qualities);
} else if ( k == 1) {
    strcpy(quality[1], qualities);
} else if ( k == 2) {
    strcpy(quality[2], qualities);
} else if ( k == 3) {
    strcpy(quality[3], qualities);
} else if ( k == 4) {
    strcpy(quality[4], qualities);
}
qualities = strtok (NULL, "\n");
k++;

用这两行:

strcpy(quality[k++], qualities);
qualities = strtok (NULL, "\n");

这是等效的代码，但它适用于任意数量的项目，最多为 quality 数组中的元素数量。

既然元素的数量是固定的，你应该改变

while (qualities != NULL)

到

while (k < N && qualities != NULL)

其中 N 是 qualities 中元素的数量。