# Getting Global Variable Value
**URL:** https://discourse.nodered.org/t/getting-global-variable-value/21727
**Category:** General
**Created:** [14 February 2020 21:43 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727 "2020-02-14T21:43:50Z")
**Posts on this page:** 18
**Page:** 1
### Author:  [@an93](https://discourse.nodered.org/u/an93)
#### Post date: [14 February 2020 21:43 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/1 "2020-02-14T21:43:50Z")
Hello,
I am having some trouble with getting the value of global variable being set, in functions. Below is the flow screenshot;
Function 4 goes:
global.set("TRIGGER",msg.payload);
var res = global.get('LENGTH');
var res1 = global.get('CABLE\_DESCRIPTION');
var res2 = global.get('FAULT\_STRING');
var res3 = global.get('TRIGGER')
if(res3===true){
msg.payload = "res"+"res1"+"res2";
}
else{
return msg[null];
}
Function 1 till 3 remain same with change in definition of global variable name.
global.set("LENGTH",msg.payload);
return msg;
What i am trying to achieve here if trigger goes high then capture the data and display it !!
Any help/recommendation would be appreciated !
---
### Author:  [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)
#### Post date: [14 February 2020 22:07 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/2 "2020-02-14T22:07:54Z")
> [@an93](#):
>
> var res = global.get('LENGTH');
> var res1 = global.get('CABLE\_DESCRIPTION');
> var res2 = global.get('FAULT\_STRING');
> var res3 = global.get('TRIGGER')
> if(res3===true){
> msg.payload = "res"+"res1"+"res2";
> }
You are trying to construct the `msg.payload` from strings, and not the variables that you created earlier...
example - `res` is a variable, `"res"` is a string
---
### Author:  [@Colin](https://discourse.nodered.org/u/Colin)
#### Post date: [14 February 2020 22:22 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/3 "2020-02-14T22:22:07Z")
> [@an93](#):
>
> return msg[null];
What does that line do? I don't think it is valid javascript, but perhaps it is some subtle syntax that I have not met so far. I wonder whether you meant to say `return null`
---
### Author:  [@an93](https://discourse.nodered.org/u/an93)
#### Post date: [14 February 2020 22:30 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/4 "2020-02-14T22:30:29Z")
@Colin, yes that's a typo.
---
### Author:  [@an93](https://discourse.nodered.org/u/an93)
#### Post date: [14 February 2020 22:33 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/5 "2020-02-14T22:33:08Z")
@Paul-Reed, how do i call the global variable then,
supposedly saying
For Ex:
global.set('LENGTH',msg.payload);
return msg
Is it supposed to be
var res = global.get('LENGTH');
---
### Author:  [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)
#### Post date: [14 February 2020 22:37 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/6 "2020-02-14T22:37:46Z")
> [@an93](#):
>
> how do i call the global variable then,
You are calling the global variables correctly, but when you are trying to create the `msg.payload` you are referring to the variables as strings, because you have added speech marks around the variable's names.
Are `res`, `res1` and `res2` numbers because you seem to be adding (+) their values together.
If `res`, `res1` and `res2` are string values, then maybe `&&` instead of `+`
---
### Author:  [@an93](https://discourse.nodered.org/u/an93)
#### Post date: [14 February 2020 22:45 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/7 "2020-02-14T22:45:38Z")
Yes res and res1 are numbers, res 3 is string, tried changing it but no luck yet
global.set('TRIGGER',msg.payload);
var res = global.get('LENGTH');
var res1 = global.get('CABLE\_DESCRIPTION');
var res2 = global.get('FAULT\_STRING');
var res3 = global.get('TRIGGER')
//var rest = msg.payload;
if(res3===false)
{
// msg.payload = "how are you";
msg.payload = res;
}
else{
return msg;
}
---
### Author:  [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)
#### Post date: [14 February 2020 22:51 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/8 "2020-02-14T22:51:00Z")
> [@an93](#):
>
> var res2 = global.get('FAULT\_STRING');
Is `res2` a string (it's called FAULT\_STRING?) if so, it's like trying to add values like;
3 + 4 + donut = ???
---
### Author:  [@an93](https://discourse.nodered.org/u/an93)
#### Post date: [14 February 2020 23:02 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/11 "2020-02-14T23:02:44Z")
global.set('TRIGGER',msg.payload);
var res = global.get('LENGTH');
var res1 = global.get('CABLE\_DESCRIPTION');
var res2 = global.get('FAULT\_STRING');
var trig = global.get('TRIGGER')
if(trig===false)
{
msg.payload = res;
}
else{
return msg;
}
res is float which should "var" as datatype
res 1 and 2 are strings for which i get your point about my datatype being wrong
---
### Author:  [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)
#### Post date: [14 February 2020 23:07 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/12 "2020-02-14T23:07:43Z")
> [@an93](#):
>
> else{
> return msg;
> }
What is the `msg` - it's not defined.
Bedtime for me 😉
---
### Author:  [@an93](https://discourse.nodered.org/u/an93)
#### Post date: [14 February 2020 23:08 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/13 "2020-02-14T23:08:58Z")
its supposed to be null if the condition does not meet
Bedtime @5 on friday. LAME !!!!!!
---
### Author:  [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)
#### Post date: [14 February 2020 23:12 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/14 "2020-02-14T23:12:10Z")
> [@an93](#):
>
> Bedtime @5 on friday. LAME !!!!!!
In UK - 23:10hrs....
---
### Author:  [@an93](https://discourse.nodered.org/u/an93)
#### Post date: [14 February 2020 23:21 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/15 "2020-02-14T23:21:31Z")
Alright in the mean time i will try \>
---
### Author:  [@an93](https://discourse.nodered.org/u/an93)
#### Post date: [14 February 2020 23:49 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/16 "2020-02-14T23:49:29Z")
@Colin how can we return the message with combination of String and variable together ?
var res = global.get('LENGTH');
var res1 = global.get('CABLE\_DESCRIPTION');
var res2 = global.get('FAULT\_STRING');
var trig = global.get('TRIGGER')
if(trig===false)
{
msg.payload = res;
return msg;
}
else
{
return msg[null];
}
---
### Author:  [@knolleary](https://discourse.nodered.org/u/knolleary)
#### Post date: [14 February 2020 23:53 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/17 "2020-02-14T23:53:41Z")
Can you clarify exactly what you want the function to return? You are getting four values from context. Describe in words what you want the result to be.
---
### Author:  [@an93](https://discourse.nodered.org/u/an93)
#### Post date: [14 February 2020 23:56 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/18 "2020-02-14T23:56:32Z")
@knolleary
Got it, that helps. Thank you ! Reached my max for today but that helped.
---
### Author:  [@knolleary](https://discourse.nodered.org/u/knolleary)
#### Post date: [15 February 2020 00:02 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/19 "2020-02-15T00:02:42Z")
Right at the start of this thread, you had the code:
```auto
global.set("TRIGGER",msg.payload);
var res = global.get('LENGTH');
var res1 = global.get('CABLE_DESCRIPTION');
var res2 = global.get('FAULT_STRING');
var res3 = global.get('TRIGGER')
if(res3===true){
msg.payload = "res"+"res1"+"res2";
}
else{
return msg[null];
}
```
As Paul pointed out, the line:
```auto
msg.payload = "res"+"res1"+"res2";
```
Will result in msg.payload having the value `"resres1res2"`. If you meant to join those three variables together, you should do:
```auto
msg.payload = res+res1+res2;
```
You will also need a `return msg` at the end so it returns the message.
> [@an93](#):
>
> The return should be message with individual values.
That doesn't help explain what format you want it to be in. I have assumed you want it to return a message with the three values joined together as a string.
If instead you want it to return a message with an object payload with the three separate values in it, you could do:
```auto
msg.payload = {
res: res,
res1: res1,
res2: res2
}
```
You would then be able to reference the individual properties later in the flow as `msg.payload.res` and `msg.payload.res1` etc.
---
### Author:  [@system](https://discourse.nodered.org/u/system)
#### Post date: [29 February 2020 00:15 UTC](https://discourse.nodered.org/t/getting-global-variable-value/21727/20 "2020-02-29T00:15:26Z")
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