我有这个
JSON对象：
{"books":[
{
"author" : "Petr","book_name" : "Test1","pages" : 200,"year" : 2002
},{
"author" : "Petr","book_name" : "Test2","pages" : 0,"year" : 0
},{
"author" : "STO","book_name" : "Rocks","pages" : 100,"year" : 2002
}
]
}
例如,我需要找一本作者密钥等于Petr的书.我怎样才能做到这一点？现在我有这段代码：
Json::Value findBook(){
Json::Value root = getRoot();
cout<<root["books"].toStyledString()<<endl; //Prints JSON array of books mentioned above
string searchKey;
cout<<"Enter search key: ";
cin>>searchKey;
string searchValue;
cout<<"Enter search value: ";
cin>>searchValue;
Json::Value foundBooks = root["books"]???; // How can I get here a list of books where searchKey is equal to searchValue?
}
提前致谢.
解决方法
这样的事应该做：
std::vector<Json::Value> booksByPeter(const Json::Value& root) {
std::vector<Json::Value> res;
for (const Json::Value& book : root["books"]) // iterate over "books"
{
if (book["author"].asString() == "Petr") // if by "Petr"
{
res.push_back(book); // take a copy
}
}
return res; // and return
}
如果不是C 11,则必须做：
const Json::Value& books = root["books"];
for (Json::ValueConstIterator it = books.begin(); it != books.end(); ++it)
{
const Json::Value& book = *it;
// rest as before
}
