如何将Javascript映射作为参数从闪电组件发送到Apex服务器控制器？

Question

I have a salesforce lightning component which enqueues server side action. To that action I need to pass a map as one of the parameters, but it looks like it takes memory address of the object instead.

The client side code that creates the map and calls the server side action:

var action = cmp.get("c.save");
var mapToSend = new Map()
for (var key of valueMap.keys()) {
    mapToSend.set(key, valueMap.get(key))
}
action.setParams({
    "name": cmp.get("v.name"),
    "params": mapToSend
});

In the controller then:

 public static Boolean save(String name, Map<String, Object> params) {

log of the javascript shows nice Map with all the correct fields, but salesforce system log shows just

14:55:16.0 (3172304)|VARIABLE_SCOPE_BEGIN|[41]|name|String|false|false
14:55:16.0 (3188041)|VARIABLE_ASSIGNMENT|[41]|name|"Account"
14:55:16.0 (3191758)|VARIABLE_SCOPE_BEGIN|[41]|params|Map<String,ANY>|true|false
14:55:16.0 (3204719)|VARIABLE_ASSIGNMENT|[41]|params|{}|0x30d2397a

Any Idea why? What those |false|false and |true|false mean in the logs?

Answer 1

The problem is with understanding the javascript data structures. The correct result is achieved by calling the apex controller with data prepared as

var mapToSend = {}
for (var key of valueMap.keys()) {
    mapToSend[key] = valueMap.get(key);
}
action.setParams({
    "name": cmp.get("v.name"),
    "params": mapToSend
});