# How to extract a value

**URL:** <https://discourse.nodered.org/t/how-to-extract-a-value/83233>\
**Category:** General\
**Tags:** node-red-dashboard\
**Created:** [27 November 2023 21:36 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233 "2023-11-27T21:36:20Z")\
**Posts on this page:** 14\
**Page:** 1

<div class="post-metadata">

**Author:** ![telescopio](https://avatars.discourse-cdn.com/v4/letter/t/bb73d2/32.png) [@telescopio](https://discourse.nodered.org/u/telescopio)\
**Post date:** [27 November 2023 21:36 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/1 "2023-11-27T21:36:20Z")

</div>

11/27/2023, 4:32:57 PM[node: debug 57](http://127.0.0.1:1880/#)  
Need help to extract the rF to show on a text node

true : msg.payload : Object

object

id: 100

tC: 26.2

tF: 79.2

---

<div class="post-metadata">

**Author:** ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)\
**Post date:** [27 November 2023 21:46 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/2 "2023-11-27T21:46:11Z")

</div>

> [@telescopio](#):
>
> Need help to extract the rF to show on a text node

rF or tF?

Change node.  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/b/4/b4723b64bd68739bf7acb74a8e9605078adc99d0.png)

Or ui-text node  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/2/0/20c85af3016c72ffd46c4ed38e0a95f961c38d05.png)

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<div class="post-metadata">

**Author:** ![Colin](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/colin/32/17040_2.png) [@Colin](https://discourse.nodered.org/u/Colin)\
**Post date:** [27 November 2023 21:54 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/3 "2023-11-27T21:54:41Z")

</div>

If you mean a node-red dashboard text node then you don't need to extract it. You can put in the Value Format field `{{msg.payload.tF}}` and the text node will pick it up from there.

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/e/5/e5a7801422582440b0f9542f2f7a85cd254ef81c.png)

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<div class="post-metadata">

**Author:** ![telescopio](https://avatars.discourse-cdn.com/v4/letter/t/bb73d2/32.png) [@telescopio](https://discourse.nodered.org/u/telescopio)\
**Post date:** [27 November 2023 22:20 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/4 "2023-11-27T22:20:25Z")

</div>

Not getting the result, here is the complete payload, need to remove under humidity the rH 70., under switch0 object the output and under temperature 100the tF 81

Thanks for your help

e 11/27/2023, 5:08:22 PM[node: debug 43](http://127.0.0.1:1880/#)

11/27/2023, 5:08:22 PM[node: debug 43](http://127.0.0.1:1880/#)

true : msg.payload : Object

object

humidity100: object

id: 100

rh: 70.7

input0: object

switch0: object

id: 0

source: "HTTP\_in"

output: false

temperature100: object

id: 100

tC: 27.2

tF: 81

---

<div class="post-metadata">

**Author:** ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)\
**Post date:** [27 November 2023 22:40 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/5 "2023-11-27T22:40:13Z")

</div>

That's completely different from what you showed before!

Humidity appears to be at msg.payload.humidity100.rh  
Temperature100 appears to be at msg.payload.temperature100.tF

You might like to view this page in the docs ([Working with messages : Node-RED](https://nodered.org/docs/user-guide/messages)) that will explain how to use the debug panel to find the right path to any data item.

Pay particular attention to the part about the buttons that appear under your mouse pointer when you over hover a debug message property in the sidebar.

![BX00Cy7yHi](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/b/d/bd1f333a9e043b061b39917c328b0094d3e52d30.gif)

To copy a debug message from Node-red to here:

- Use the Copy value button in the debug panel.
- On a new line here, click the `</>` button
- Paste your debug output over the top of `type or paste code here`

---

<div class="post-metadata">

**Author:** ![telescopio](https://avatars.discourse-cdn.com/v4/letter/t/bb73d2/32.png) [@telescopio](https://discourse.nodered.org/u/telescopio)\
**Post date:** [27 November 2023 22:40 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/6 "2023-11-27T22:40:53Z")

</div>

Not getting the result, here is the complete payload, need to remove under humidity the rH 70., under switch0 object the output and under temperature 100the tF 81

Thanks for your help

e 11/27/2023, 5:08:22 PM[node: debug 43](http://127.0.0.1:1880/#)

11/27/2023, 5:08:22 PM[node: debug 43](http://127.0.0.1:1880/#)

true : msg.payload : Object

object

humidity100: object

id: 100

rh: 70.7

input0: object

switch0: object

id: 0

source: "HTTP\_in"

output: false

temperature100: object

id: 100

tC: 27.2

tF: 81

---

<div class="post-metadata">

**Author:** ![telescopio](https://avatars.discourse-cdn.com/v4/letter/t/bb73d2/32.png) [@telescopio](https://discourse.nodered.org/u/telescopio)\
**Post date:** [27 November 2023 22:45 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/7 "2023-11-27T22:45:03Z")

</div>

```auto
{"humidity100":{"id":100,"rh":70.7},"input0":{"id":0,"state":false},"switch0":{"id":0,"source":"HTTP_in","output":false,"temperature":{"tC":55.9,"tF":132.6}},"temperature100":{"id":100,"tC":27.2,"tF":81}}

```

This what you need, let me know I am new in this

---

<div class="post-metadata">

**Author:** ![telescopio](https://avatars.discourse-cdn.com/v4/letter/t/bb73d2/32.png) [@telescopio](https://discourse.nodered.org/u/telescopio)\
**Post date:** [27 November 2023 22:47 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/8 "2023-11-27T22:47:54Z")

</div>

```auto
{"humidity100":{"id":100,"rh":70.7},"input0":{"id":0,"state":false},"switch0":{"id":0,"source":"HTTP_in","output":false,"temperature":{"tC":55.9,"tF":132.6}},"temperature100":{"id":100,"tC":27.2,"tF":81}}

```

Edit by moderator...

```auto
{
   "humidity100":{
      "id":100,
      "rh":70.7
   },
   "input0":{
      "id":0,
      "state":false
   },
   "switch0":{
      "id":0,
      "source":"HTTP_in",
      "output":false,
      "temperature":{
         "tC":55.9,
         "tF":132.6
      }
   },
   "temperature100":{
      "id":100,
      "tC":27.2,
      "tF":81
   }
}
  

```

---

<div class="post-metadata">

**Author:** ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)\
**Post date:** [27 November 2023 22:58 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/9 "2023-11-27T22:58:23Z")

</div>

Take a look at this little flow. Copy the code and Import it to your Node-red using the hamburger menu at top right.  
The inject node sends the data you posted above.  
The humidity and temperature values are shown in the debug panel and also on your dashboard - a tab called "Demo"  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/a/9/a93ca8c2aa554ea1bf396f52330eec78aa507e9e.png)

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/e/8/e8f6d95ef41df44ff34a1fc385fa91fc860aac76.png)

```auto
[{"id":"284e77e50696f6b7","type":"inject","z":"9cb3e1de8a8591ed","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"humidity100\":{\"id\":100,\"rh\":70.7},\"input0\":{\"id\":0,\"state\":false},\"switch0\":{\"id\":0,\"source\":\"HTTP_in\",\"output\":false,\"temperature\":{\"tC\":55.9,\"tF\":132.6}},\"temperature100\":{\"id\":100,\"tC\":27.2,\"tF\":81}}","payloadType":"json","x":470,"y":140,"wires":[["5c89803615097fdb","52e682394eba6ead","01803d8dde9adb15","857e2099b4aa32c7"]]},{"id":"5c89803615097fdb","type":"debug","z":"9cb3e1de8a8591ed","name":"msg.payload.humidity100.rh","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload.humidity100.rh","targetType":"msg","statusVal":"","statusType":"auto","x":680,"y":80,"wires":[]},{"id":"52e682394eba6ead","type":"debug","z":"9cb3e1de8a8591ed","name":"msg.payload.temperature100.tF","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload.temperature100.tF","targetType":"msg","statusVal":"","statusType":"auto","x":690,"y":200,"wires":[]},{"id":"01803d8dde9adb15","type":"ui_text","z":"9cb3e1de8a8591ed","group":"f149abdd741ca58e","order":1,"width":"3","height":"1","name":"","label":"Humidity","format":"{{payload.humidity100.rh}}","layout":"row-left","className":"","style":false,"font":"","fontSize":16,"color":"#000000","x":660,"y":120,"wires":[]},{"id":"857e2099b4aa32c7","type":"ui_text","z":"9cb3e1de8a8591ed","group":"f149abdd741ca58e","order":1,"width":"3","height":"1","name":"","label":"Temperature (F)","format":"{{payload.temperature100.tF}}","layout":"row-left","className":"","style":false,"font":"","fontSize":16,"color":"#000000","x":680,"y":160,"wires":[]},{"id":"f149abdd741ca58e","type":"ui_group","name":"Demo","tab":"1caa8458.b17814","order":1,"disp":true,"width":"12","collapse":false,"className":"test"},{"id":"1caa8458.b17814","type":"ui_tab","name":"Demo","icon":"dashboard","order":10,"disabled":false,"hidden":false}]

```

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<div class="post-metadata">

**Author:** ![telescopio](https://avatars.discourse-cdn.com/v4/letter/t/bb73d2/32.png) [@telescopio](https://discourse.nodered.org/u/telescopio)\
**Post date:** [27 November 2023 23:19 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/10 "2023-11-27T23:19:46Z")

</div>

Thanks that work, I apply the same logic to this output and it show on the text node, but I need CLOSE instead of False. I try a Change note before the Text node but is not working. How can convert it?

---

<div class="post-metadata">

**Author:** ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)\
**Post date:** [27 November 2023 23:28 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/11 "2023-11-27T23:28:39Z")

</div>

Export your change node (select just that node, press CTRL E, copy to clipboard) and post it here please.

---

<div class="post-metadata">

**Author:** ![telescopio](https://avatars.discourse-cdn.com/v4/letter/t/bb73d2/32.png) [@telescopio](https://discourse.nodered.org/u/telescopio)\
**Post date:** [27 November 2023 23:44 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/12 "2023-11-27T23:44:10Z")

</div>

```auto
[
    {
        "id": "706b2169406f637e",
        "type": "change",
        "z": "715181ab53ed78d9",
        "name": "",
        "rules": [
            {
                "t": "change",
                "p": "payload",
                "pt": "msg",
                "from": "false",
                "fromt": "str",
                "to": "CLOSE",
                "tot": "str"
            }
        ],
        "action": "",
        "property": "",
        "from": "",
        "to": "",
        "reg": false,
        "x": 3640,
        "y": 540,
        "wires": [
            [
                "bfd81f2d98cd1008"
            ]
        ]
    }
]

```

---

<div class="post-metadata">

**Author:** ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)\
**Post date:** [27 November 2023 23:56 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/13 "2023-11-27T23:56:05Z")

</div>

If you look at your debug output, you can see that msg.payload.switch0.output does not have quotes round the value `false` The datatype is boolean not string.  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/7/5/751e3292d0eae0db133c18cf88e584b1a08d41a5.png)

You have to amend your change node  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/c/0/c0d9041b05ef0fb2424940daeb7c5d11313d9d5c.png)

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [26 January 2024 23:56 UTC](https://discourse.nodered.org/t/how-to-extract-a-value/83233/14 "2024-01-26T23:56:44Z")

</div>

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