cJSON錯誤，編印文件

Question

我最近通過Cmake安裝由David寶潔的cJSON庫，我收到以下錯誤：

 
gcc prueba.c -lm -o prueba 
/tmp/ccdmegU5.o: In function `main': 
prueba.c:(.text+0x2e): undefined reference to `cJSON_Parse' 
prueba.c:(.text+0x45): undefined reference to `cJSON_GetObjectItem' 
prueba.c:(.text+0x60): undefined reference to `cJSON_GetObjectItem' 
prueba.c:(.text+0xa2): undefined reference to `cJSON_GetObjectItem' 
prueba.c:(.text+0xb2): undefined reference to `cJSON_GetArraySize' 
prueba.c:(.text+0xdb): undefined reference to `cJSON_GetArrayItem' 
prueba.c:(.text+0xf2): undefined reference to `cJSON_GetObjectItem' 
prueba.c:(.text+0x10d): undefined reference to `cJSON_GetObjectItem' 
prueba.c:(.text+0x146): undefined reference to `cJSON_Delete' 
collect2: error: ld returned 1 exit status 

雖然試圖編譯這樣一個簡單的.c代碼：

int main(int argc, const char * argv[]) { 

/*{ 
    "name": "Mars", 
    "mass": 639e21, 
    "moons": [ 
     { 
      "name": "Phobos", 
      "size": 70 
     }, 
     { 
      "name": "Deimos", 
      "size": 39 
     } 
    ] 
}*/ 
char *strJson = "{\"name\" : \"Mars\",\"mass\":639e21,\"moons\":[{\"name\":\"Phobos\",\"size\":70},{\"name\":\"Deimos\",\"size\":39}]}"; 

printf("Planet:\n"); 
// First, parse the whole thing 
cJSON *root = cJSON_Parse(strJson); 
// Let's get some values 
char *name = cJSON_GetObjectItem(root, "name")->valuestring; 
double mass = cJSON_GetObjectItem(root, "mass")->valuedouble; 
printf("%s, %.2e kgs\n", name, mass); // Note the format! %.2e will print a number with scientific notation and 2 decimals 
// Now let's iterate through the moons array 
cJSON *moons = cJSON_GetObjectItem(root, "moons"); 
// Get the count 
int moons_count = cJSON_GetArraySize(moons); 
int i; 
for (i = 0; i < moons_count; i++) { 
    printf("Moon:\n"); 
    // Get the JSON element and then get the values as before 
    cJSON *moon = cJSON_GetArrayItem(moons, i); 
    char *name = cJSON_GetObjectItem(moon, "name")->valuestring; 
    int size = cJSON_GetObjectItem(moon, "size")->valueint; 
    printf("%s, %d kms\n", name, size); 
} 

// Finally remember to free the memory! 
cJSON_Delete(root); 
return 0; 
} 

如果我將cJSON.c的內容添加到我的代碼中，它可以解決問題，但會打印損壞的文件。

Answer 1

您需要使用-lcjson進行編譯，以將您的代碼與已安裝的cJSON庫鏈接。