Concatenate several columns

[LarsAkut]

Hi

I have a table with a lot of columns. I would like to connect them to 1 string. It's for an API where i only need this string.

i have a "set" for each articel. Varenummer 123456 and LeverandoerAO has to bee connected like this, 123456AO.  and then seperated by a comma and then Antal. So 3 columns is used for 1 article. And i need this for 25 articels(eash has 3 columns to make the string correct.

I have tried Concatenate it like this but it leaves me with commas and semicolon that are not used.

Concatenate(

[1 Varenummer],[1 Leverandør],":",[1 Antal],",",

[2 Varenummer],[2 Leverandør],":",[2 Antal],",",

[3 Varenummer],[3 Leverandør],":",[3 Antal],",",

[4 Varenummer],[4 Leverandør],":",[4 Antal],",",

[5 Varenummer],[5 Leverandør],":",[5 Antal],",",

)

Heres is the output 

273041032AO:2,744760650AO:2,744760638AO:1,744760617AO:2,:,:,:,:,:,

How would the formula look so i only makes a string if Varenummer is Not empty?

[SkrOYC]

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