When working with multi-select choice columns in SharePoint, there may be scenarios where you want to display and update the selected choices dynamically within a form. This workaround will help you display multi-select choices in a task form and ensure that any updates made in the form are reflected in SharePoint.
Step 1:
Use an “Apply a Regular Expression” and insert the SharePoint choice column in the input text. If you are using a column from your start event object, use the following expression below and output it in a collection variable:

If you are using a SharePoint Online Object (for example if you retrieved an item or queried a list), use the following expression:

We are basically splitting the currently selected choices in SharePoint into a collection, so we can use it on the task form.
Step 2:
Edit the task form, drag and drop a new Choice - Multiple control and populate the options field with the same options from the choice column in SharePoint.

Insert the collection variable (located in the user defined variables tab) from step 1 into the default value field:

We are now done with displaying the selected choices from SharePoint into our Nintex Automation Cloud task form.
Saving back to SharePoint
If you require changes to be made on the task form and need to save the changes back into SharePoint, simply use an Update items action and insert the choice control from your task into your choice/multiselect column in SharePoint:
