Merge pull request #12641 from dkurt:dnn_samples_args_autofill

modules/core/include/opencv2/core/persistence.hpp

@@ -542,6 +542,11 @@ public:
     */
     CV_WRAP_AS(at) FileNode operator[](int i) const;
 
+    /** @brief Returns keys of a mapping node.
+    @returns Keys of a mapping node.
+     */
+    CV_WRAP std::vector<String> keys() const;
+
     /** @brief Returns type of the node.
     @returns Type of the node. See FileNode::Type
      */

modules/core/src/persistence_cpp.cpp

@@ -269,6 +269,20 @@ FileNode FileNode::operator[](int i) const
         i == 0 ? *this : FileNode();
 }
 
+std::vector<String> FileNode::keys() const
+{
+    std::vector<String> res;
+    if (isMap())
+    {
+        res.reserve(size());
+        for (FileNodeIterator it = begin(); it != end(); ++it)
+        {
+            res.push_back((*it).name());
+        }
+    }
+    return res;
+}
+
 String FileNode::name() const
 {
     const char* str;