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純C 存取JSON(使用cJSON函式庫)   資料來源: http://sourceforge.net/projects/cjson/   範例程式 #include #include #include #include “cJSON.h” char * create1() {      cJSON *root,*dir1,*dir2,*dir3;      char *out;      // 創建json陣列型結構體      root = cJSON_CreateArray();      // 為陣列添加物件      cJSON_AddItemToArray(root,dir1=cJSON_CreateObject());      // 為物件添加字串鍵值對      cJSON_AddStringToObject(dir1,”name”,”.”);      cJSON_AddStringToObject(dir1,”path”,”uploads/”);      cJSON_AddStringToObject(dir1,”flag”,”true”);      cJSON_AddItemToArray(root,dir2=cJSON_CreateObject());      cJSON_AddStringToObject(dir2,”name”,”..”);      cJSON_AddStringToObject(dir2,”path”,”uploads”);      cJSON_AddStringToObject(dir2,”flag”,”true”);      cJSON_AddItemToArray(root,dir3=cJSON_CreateObject());      cJSON_AddStringToObject(dir3,”name”,”wang.txt”);      cJSON_AddStringToObject(dir3,”path”,”uploads/wang.txt”);      cJSON_AddStringToObject(dir3,”flag”,”false”);      // 將json結構體轉換為字串      out=cJSON_Print(root);      // 刪除      cJSON_Delete(root);      return out; }   char * create2() {      cJSON *root,*dir,*subdir,*dir1,*dir2,*dir3;      char *out;      root=cJSON_CreateObject();        cJSON_AddItemToObject(root,”Root”,dir=cJSON_CreateObject());      cJSON_AddStringToObject(dir,”name”,”/”);      cJSON_AddStringToObject(dir,”path”,”/”);      cJSON_AddStringToObject(dir,”flag”,”true”);        cJSON_AddItemToObject(root,”Child”,subdir = cJSON_CreateArray());      cJSON_AddItemToObject(subdir,”dira”,dir1=cJSON_CreateObject());      cJSON_AddStringToObject(dir1,”name”,”.”);      cJSON_AddStringToObject(dir1,”path”,”/./”);      cJSON_AddStringToObject(dir1,”flag”,”true”);      cJSON_AddItemToObject(subdir,”dira”,dir2=cJSON_CreateObject());      cJSON_AddStringToObject(dir2,”name”,”..”);      cJSON_AddStringToObject(dir2,”path”,”/../”);      cJSON_AddStringToObject(dir2,”flag”,”true”);      cJSON_AddItemToObject(subdir,”dira”,dir3=cJSON_CreateObject());      cJSON_AddStringToObject(dir3,”name”,”uploads”);      cJSON_AddStringToObject(dir3,”path”,”/uploads/”);      cJSON_AddStringToObject(dir3,”flag”,”true”);        out=cJSON_Print(root);      cJSON_Delete(root);      return out; }     char * create3() {      cJSON *root,*img,*thm;      char *out;      int nums[4]={100,200,300,400};      root=cJSON_CreateObject();      cJSON_AddItemToObject(root, “Root”, img=cJSON_CreateObject());      cJSON_AddNumberToObject(img,”key”,800);      cJSON_AddNumberToObject(img,”value”,600);      cJSON_AddStringToObject(img,”Title”,”Sugon”);      cJSON_AddItemToObject(img,”child”,thm=cJSON_CreateObject());      cJSON_AddNumberToObject(thm,”key”,125);      cJSON_AddStringToObject(thm,”value”,”100″);          cJSON_AddStringToObject(thm,”Url”,”www.sugon.com”);      cJSON_AddItemToObject(img,”nums”, cJSON_CreateIntArray(nums,4));      out=cJSON_Print(root);      cJSON_Delete(root);      return out; }   char * create4() {      cJSON *root,*dir1,*dir2;      char *out;      const char *ro = “Root”;      root=cJSON_CreateObject();      cJSON_AddItemToObject(root,ro,dir1=cJSON_CreateArray());      cJSON_AddNumberToObject(dir1,”key”,800);      cJSON_AddNumberToObject(dir1,”value”,600);      cJSON_AddStringToObject(dir1,”Title”,”key and value”);      cJSON_AddItemToObject(root,ro,dir2=cJSON_CreateArray());      cJSON_AddNumberToObject(dir2,”value”,125);      cJSON_AddStringToObject(dir2,”key”,”100″);      cJSON_AddStringToObject(dir2,”Title”,”value and key”);      out=cJSON_Print(root);      cJSON_Delete(root);      return out; }   void parse1(char *out) {      cJSON * root,*arrayItem,*item,*name,*path,*flag;      int i = 0,size = 0;      char *pr = NULL,*na = NULL,*pa = NULL,*fl = NULL;        // 將字串解析成json結構體      root = cJSON_Parse(out);      // 根據結構體獲取陣列大小      size = cJSON_GetArraySize(root);      //printf(“%d\n”,size);      // 遍歷數組      for(i=0;i      {          //獲取第i個陣列項          arrayItem = cJSON_GetArrayItem(root,i);          if(arrayItem)          {               //printf(“%s\n”,”start……”);               //講json結構體轉換成字串               pr = cJSON_Print(arrayItem);               item = cJSON_Parse(pr);               name = cJSON_GetObjectItem(item,”name”);               path = cJSON_GetObjectItem(item,”path”);               flag = cJSON_GetObjectItem(item,”flag”);               na = cJSON_Print(name);               pa = cJSON_Print(path);               fl = cJSON_Print(flag);               //printf(“%s\n”,pr);               printf(“name:%s\n”,na);               printf(“path:%s\n”,pa);               printf(“flag:%s\n\n”,fl);          }      } }   void parse2(char *out) {      cJSON * root,*Root,*Child,*arrayItem,*item,*name,*path,*flag;      int i = 0,size = 0;      char *pr = NULL,*na = NULL,*pa = NULL,*fl = NULL;      root = cJSON_Parse(out);      if(root)      {          Root = cJSON_GetObjectItem(root,”Root”);          if(Root)          {               name = cJSON_GetObjectItem(Root,”name”);               path = cJSON_GetObjectItem(Root,”path”);               flag = cJSON_GetObjectItem(Root,”flag”);               na = cJSON_Print(name);               pa = cJSON_Print(path);               fl = cJSON_Print(flag);               printf(“Root:\n”);               printf(“name:%s\n”,na);               printf(“path:%s\n”,pa);               printf(“flag:%s\n\n”,fl);          }          Child = cJSON_GetObjectItem(root,”Child”);          if(Child)          {               size = cJSON_GetArraySize(Child);               //printf(“%d\n”,size);               printf(“Child:\n”);               for(i=0;i               {                    arrayItem = cJSON_GetArrayItem(Child,i);                    if(arrayItem)                    {                        //printf(“%s\n”,”start……”);                        pr = cJSON_Print(arrayItem);                        item = cJSON_Parse(pr);                        name = cJSON_GetObjectItem(item,”name”);                        path = cJSON_GetObjectItem(item,”path”);                        flag = cJSON_GetObjectItem(item,”flag”);                        na = cJSON_Print(name);                        pa = cJSON_Print(path);                        fl = cJSON_Print(flag);                        //printf(“%s\n”,pr);                        printf(“name:%s\n”,na);                        printf(“path:%s\n”,pa);                        printf(“flag:%s\n\n”,fl);                    }               }          }      } }   int main() {      char *out1 = create1();      char *out2 = create2();      char *out3 = create3();      char *out4 = create4();      printf(“%s\n\n\n”,out1);      parse1(out1);      printf(“%s\n\n\n”,out2);      parse2(out2);      printf(“%s\n\n\n”,out3);      printf(“%s\n\n\n”,out4);      return 0; }