var nodeArray = "";var nodesObj = mytree.getChecked();var i;var length=nodesObj .length;for (i = 0; i < length; i++) {nodeArray += nodesObj[i].id + ',';   //允许多选的情况。如果不允许多选，就直接nodesObj[i].id }nodeArray = nodeArray.substring(0, nodeArray.length - 1); 

[{"text": "To Do", "cls": "folder","expanded": true,"children": [{"text": "Go jogging","leaf": true,"checked": true},{"text": "Take a nap","leaf": true,"checked": false},{"text": "Climb Everest","leaf": true,"checked": false}]},{"text": "Grocery List","cls": "folder","children": [{"text": "Bananas","leaf": true,"checked": false},{"text": "Milk","leaf": true,"checked": false},{"text": "Cereal","leaf": true,"checked": false},{"text": "Energy foods","cls": "folder","children": [{"text": "Coffee","leaf": true,"checked": false},{"text": "Red Bull","leaf": true,"checked": false}]}]},{"text": "Remodel Project", "cls": "folder","children": [{"text": "Finish the budget","leaf": true,"checked": false},{"text": "Call contractors","leaf": true,"checked": false},{"text": "Choose design","leaf": true,"checked": false}]}]