我在使用 C++ 中的 boost 库和属性树创建 json 数组时遇到了麻烦。
我引用了this线程,尤其是这部分
ptree pt;
ptree children;
ptree child1, child2, child3;
child1.put("childkeyA", 1);
child1.put("childkeyB", 2);
child2.put("childkeyA", 3);
child2.put("childkeyB", 4);
child3.put("childkeyA", 5);
child3.put("childkeyB", 6);
children.push_back(std::make_pair("", child1));
children.push_back(std::make_pair("", child2));
children.push_back(std::make_pair("", child3));
pt.put("testkey", "testvalue");
pt.add_child("MyArray", children);
write_json("test2.json", pt);
结果:
{
"testkey": "testvalue",
"MyArray":
[
{
"childkeyA": "1",
"childkeyB": "2"
},
{
"childkeyA": "3",
"childkeyB": "4"
},
{
"childkeyA": "5",
"childkeyB": "6"
}
]
}
但是如果我只想实现一个没有任何对象包含它的简单数组,我该怎么办呢?像这样:
[
{
"childkeyA": "1",
"childkeyB": "2"
},
{
"childkeyA": "3",
"childkeyB": "4"
},
{
"childkeyA": "5",
"childkeyB": "6"
}
]
非常感谢。
最佳答案
关于 JSON 支持的 Boost 文档只有几行:
The property tree dataset is not typed, and does not support arrays as such. Thus, the following JSON / property tree mapping is used:
- JSON objects are mapped to nodes. Each property is a child node.
- JSON arrays are mapped to nodes. Each element is a child node with an empty name. If a node has both named and unnamed child nodes, it cannot be mapped to a JSON representation.
- JSON values are mapped to nodes containing the value. However, all type information is lost; numbers, as well as the literals "null", "true" and "false" are simply mapped to their string form.
- Property tree nodes containing both child nodes and data cannot be mapped.
JSON round-trips, except for the type information loss.
突出显示我的
关于c++ - 使用 boost property_tree 创建 json 数组,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/43324370/