What is the concept of IEnumerable <object> variable for Read Column?

What is the concept of IEnumerable variable for Read Column ? What is IEnumerable variable ? I am new to coding ans UiPath. Can anybody explain me in a easy way ?


To keep it simple, if your object implement IEnumerable, you can iterate over it (with a ForEach). In other words, if something gives you an IEnumerable it provides you a mean to have its elements one by one.

I’m quite new to VB and .NET (for UiPath purposes) but I’m quite sure that ForEach expects that the objects it iterate over implement IEnumerable and an object implementing IEnumerable is able to give next element and tell that the end is reached.

Implementing an Interface is like swearing that “I guarantee that I have the methods in the contract called IEnumerable and the products are conform to that contract”.

ForEach doesn’t require a specific object type but any object that implements that Interface.

There is a lot to tell so if you need to dig into one particular aspect, please tell me.


@Gaurab, yes @msan couldn’t have said it better, so the word enumerate means list things one by one. so think of enumeration as a collection or an ordered list of things that can be listed each at a time. though It does not allow access to the random positions of the collection like you cannot access elements using an index like you would do with arrays and lists, you can only browse sequentially or return to the beginning.


Hello, i am very new to Uipath, almost 2 weeks :slight_smile: i am trying to read a column. But it takes everything as a letter.

For example in column A1, it writes “SIRA” but it reads as “S”, “I”, “R”, “A”.

So, i try to find a solution from the internet. And i use IENumerable, but this time i have;

I dont know what to do. What is the problem in here. Could you please help me?

This error indicates that your variable readColumnOutput is not initialized.
Check out below link.
Read from excel file

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Hi, I have a column in Excel with string values from which I am trying to extract only the numbers. I am using “Matches” activity and the Output is IEnumerator. Can you please help me out with this. Below is my workflow from the for each activity:

Hello, thank you so much for your help :slight_smile:

any solution?

how i solve this error


I have a guess but please open a new thread and provide context.