问题描述
如何正确使用Scott Klement的YAJL库来读取Watson Visual Recognition的响应? json对象如下所示:
{
"images": [
{
"classifiers": [
{
"classifier_id": "default","name": "default","classes": [
{
"class": "outside mirror","score": 0.85,"type_hierarchy": "/reflector/mirror/outside mirror"
},{
"class": "mirror","score": 0.998
},{
"class": "reflector",{
"class": "car mirror","score": 0.764,"type_hierarchy": "/reflector/mirror/car mirror"
},{
"class": "rearview mirror","score": 0.714,"type_hierarchy": "/reflector/mirror/rearview mirror"
},{
"class": "ash grey color","score": 0.778
},{
"class": "bottle green color","score": 0.532
}
]
}
],"source_url": "https://.jpg","resolved_url": "https://.jpg"
}
],"images_processed": 1,"custom_classes": 0
}
现在,我想从具有类score_hierarchy的classes对象中获取值。 我怎样才能进入类数组? 获取图像对象后,我找不到分类器以继续...
docNode = yajl_stmf_load_tree( temporaryFile: errMsg);
if errMsg <> '';
return imageClasses;
endif;
i = 0;
images = YAJL_OBJECT_FIND(docNode: 'images');
dow yajl_array_loop(images: i: node);
// Todo: How to continue to get "classifiers" object?
j = 0;
dow yajl_object_loop(node:j:key:val);
select;
when key = 'classes';
imageClasses(i).class = yajl_get_string(val);
when key = 'score';
imageClasses(i).score = yajl_get_number(val);
when key = 'type_hierarchy';
imageClasses(i).typeHierarchy = yajl_get_string(val);
endsl;
enddo;
enddo;
yajl_tree_free(docNode);
解决方法
我认为应该这样做:
docNode = yajl_stmf_load_tree( temporaryFile: errMsg);
if errMsg <> '';
return imageClasses;
endif;
i = 0;
images = YAJL_OBJECT_FIND(docNode: 'images');
dow yajl_array_loop(images: i: node);
classifiers = YAJL_OBJECT_FIND(node: 'classifiers');
j = 0;
dow yajl_object_loop(classifiers:j:key:val);
select;
when key = 'classes';
imageClasses(i).class = yajl_get_string(val);
when key = 'score';
imageClasses(i).score = yajl_get_number(val);
when key = 'type_hierarchy';
imageClasses(i).typeHierarchy = yajl_get_string(val);
endsl;
enddo;
enddo;
yajl_tree_free(docNode);
如果需要更多示例,此页面提供了更多信息: https://www.fieldexit.com/forum/display?threadid=199
,这是现在可以使用的代码:
images = YAJL_OBJECT_FIND(docNode: 'images');
i = 0;
dow yajl_array_loop(images: i: node);
classifiers = YAJL_OBJECT_FIND(node: 'classifiers');
k = 0;
dow yajl_array_loop(classifiers: k: node);
classes = YAJL_OBJECT_FIND(node: 'classes');
j = 0;
dow yajl_array_loop(classes: j: node);
val = YAJL_object_find(node:'class');
imageClasses.classes(j).class = yajl_get_string(val);
val = YAJL_object_find(node:'score');
imageClasses.classes(j).score = yajl_get_number(val);
val = YAJL_object_find(node:'type_hierarchy');
imageClasses.classes(j).typeHierarchy = yajl_get_string(val);
enddo;
enddo;
enddo;