how to add current domain name on a sales order page with the help of transactionbody field to achieve this
first we need to add the custom field in the

Add a custom field in the Sales order and fill the field with value from website.

step 1:

Create a transaction body field. Customization -> List,Records&Fields -> Transaction body fields -> new

step 2:

Add the created custom transaction body field in the configuration record. Otherwise we cannot get that field in the consoles

step 3:

Using SetTrasactionBodyField property we can add the value to this field.

For more information of SetTrasactionBodyField refer the link:
https://system.netsuite.com/help/helpcenter/en_US/APIs/SuiteCommerce/Extensibility/Frontend/index.html