Change type of a list column using workflow

Question

I want to change column type of a Survey List from 'choice' to 'single line of text' and again from 'single line of text' to 'choice' in a Sharepoint 2013 Designer workflow. Is it possible ?

Answer 1

From SharePoint Designer perspective, it is possible using call web service action (assuming you are using SharePoint 2013 workflow). If you are using SharePoint 2010 Workflow, then you could use this solution to achieve that.

Then you could build a custom web service and do the change column type process inside the code, and call the web service from the workflow, for example (not tested) :

    private static void ChangeFieldType() {
        SPSecurity.RunWithElevatedPrivileges(delegate() {
            using (SPSite site = new SPSite("http://yoursite.com")) {
                using (SPWeb web = site.OpenWeb() {
                    try {
                        web.AllowUnsafeUpdates = true;
                        SPList list = web.Lists["YourList"];
                        SPField changeTypeField = list.Fields["YourField"];
                        string schema;
                        schema = changeTypeField.SchemaXml;
                        schema = schema.Replace("Type=\"Choice\"", "Type=\"Text\"");
                        changeTypeField.SchemaXml = schema;
                        changeTypeField.Update();
                        web.AllowUnsafeUpdates = false;
                    } catch (Exception e) {
                        Console.WriteLine(e.Message);
                    }
                }
            }
        });
    }

Since Nintex Workflow also provides functionality to call a web service, I think it is also possible to do it using Nintex Call Web Service Action.