Node-red：从 msg.payload 获取值并将其保存在变量中

Question

how can I take the value from msg.payload and put it inside variable then I can use this variable in different functions (node-red)

Answer 1

Each msg is just a javascript object, and using msg.payload to contain the data a node operates on is really more of a convention than a hard rule (ie: most of the nodes in node-red look for data in the msg.payload field). However, you can also attach data to any other property in the msg object, with the exception of the id field.

When you pass that message from one node to another, you can then access your stored data using the msg object.

If you store a query in msg.query , for example, you can access it in a subsequent node in the flow by just accessing the msg.query object.

Answer 2

Add this to a function node:

global.set("Variable_name_here",msg.payload);

This will store the msg.paylog (received on the input of the node) to a global variable that can be used at any time, from any flow.

In order to use the variable add this to a function node: var M =global.get("Variable_name_here");

This will set the global variable value to the local variable M, to be used in your node.