C和json是非常常用的編程語言，在實際開發過程中，經常需要進行json格式數據的解析操作。json數據結構相對簡單，但是當遇到深度較深、結構比較復雜的json數據時就需要進行多層解析。

在多層解析過程中，我們需要根據json數據的結構分層解析。C語言為我們提供了許多操作字符串的函數，比如strlen、strcpy、strcat等，這些函數非常適合實現json的多層解析操作。

//以{"person":{"name":"John","age":30,"array":["apple","banana"]}}為例
char *json_str = "{\"person\":{\"name\":\"John\",\"age\":30,\"array\":[\"apple\",\"banana\"]}}";
char *name, *array1, *array2;
int age;
//第一層解析：獲取person結構體
char *person = strstr(json_str, "\"person\":{");
if (person) {
//第二層解析：獲取name屬性
name = strstr(person, "\"name\":\"");
if (name) {
name += strlen("\"name\":\"");
char *temp = strstr(name, "\"");
int len = temp - name;
strncpy(name, name, len);
name[len] = '\0';
printf("name: %s\n", name);
}
//第二層解析：獲取age屬性
char *age_str = strstr(person, "\"age\":");
if (age_str) {
age_str += strlen("\"age\":");
char *temp = strstr(age_str, ",");
if (!temp) {
temp = strstr(age_str, "}");
}
int len = temp - age_str;
char *temp_str = (char *)malloc(len + 1);
strncpy(temp_str, age_str, len);
temp_str[len] = '\0';
age = atoi(temp_str);
free(temp_str);
printf("age: %d\n", age);
}
//第二層解析：獲取array屬性
char *array_str = strstr(person, "\"array\":[");
if (array_str) {
array_str += strlen("\"array\":[");
char *left = strstr(array_str, "\"");
char *right = strstr(array_str, "\",\"");
right += strlen("\",\"");
char *temp = strstr(right, "\"]");
int len = temp - right;
array1 = (char *)malloc(len + 1);
strncpy(array1, right, len);
array1[len] = '\0';
printf("array1: %s\n", array1);
left = right;
right = strstr(right, "\",\"");
right += strlen("\",\"");
temp = strstr(right, "\"]");
len = temp - right;
array2 = (char *)malloc(len + 1);
strncpy(array2, right, len);
array2[len] = '\0';
printf("array2: %s\n", array2);
}
}

以上代碼就是一個簡單的多層解析例子。在實際應用中需要根據具體的json數據結構來設計多層解析。