After discovering the DataTypeService, and realising that I needed the internal Id of the prevalue rather than the string value I'd assigned it.. I've put together the following solution - unsure if I've done it 'right' but works for me..

ContentService c = new ContentService();

// Fetch the content I'm updating..
IContent myContent = c.GetById(1054);

// I need to find the Id of the 'Reserved' prevalue option on the Status data type I created
DataTypeService dts = new DataTypeService();

// Get an instance of the status editor
var statusEditor = dts.GetAllDataTypeDefinitions().First(x => x.Name == "Status");

// Now we can fetch the pre-values collection, and use linq to find the Id for the 'Reserved' option
int preValueId = dts.GetPreValuesCollectionByDataTypeId(statusEditor.Id).PreValuesAsDictionary.Where(d => d.Value.Value == "Reserved").Select(f => f.Value.Id).First();

myContent.SetValue("status", preValueId); // Finally update the status with the new Id.


c.SaveAndPublishWithStatus(kit); // All done, save and publish

Hope this helps someone get on the right track - feel free to comment with amends if I've done anything daft.

This is the answer that I've been looking for! thank god someone posted it in here I can't find anything on the net.

did you find the way just by using the Name instead of the Id?

After many weeks of searching, i found this thread and this was 100% the solution i needed. Thank you so much!

Could you by any chance set your own answer as the correct one, since that makes it easier for people to find.

This is very complicated really.

What I have done is made a custom property editor for 'Dropdown' which just stores the selected value as a string.

Then I can set or retrieve the value just as a string without having to translate it.

Hello, I use a similar method has been said above but I have an error overload

note that once the proprty is set using the string value, you need to reset it manually through the backoffice, otherwise using the preValueId still doesn't work :(

Hi Guys,

Here are some useful methods a wrote. Sure they will come in handy....

public static int GetDataTypeId(string dataTypeName)
        {
            var dataTypeService = ApplicationContext.Current.Services.DataTypeService;
            var allTypes = dataTypeService.GetAllDataTypeDefinitions();
            return allTypes.First(x => dataTypeName.InvariantEquals(x.Name)).Id;
        }

public static PreValueCollection GetPreValues(string dataTypeName)
        {
            int dataTypeId = GetDataTypeId(dataTypeName);
            var dts = ApplicationContext.Current.Services.DataTypeService;
            var preValues = dts.GetPreValuesCollectionByDataTypeId(dataTypeId);
            return preValues;
        }

public static List<SelectListItem> PreValuesToSelectList(string dataTypeName)
        {
            return (from x in GetPreValues(dataTypeName).PreValuesAsDictionary
                    select new SelectListItem
                    {
                        Text = x.Value.Value,
                        Value = x.Value.Id.ToString()
                    }).ToList();
        }


public static string GetPreValueString(string preValueId)
        {
            int Id;
            if(int.TryParse(preValueId, out Id))
            {
                return library.GetPreValueAsString(Id);
            }

            return string.Empty;
        }

Hi All,

I do the same scenario in Umbraco version 8.1.0 so, How I can bind selected value in content node value and display in the back office?

var registrationContent = _contentService.Create(model.FullName, 1497, "registration"); registrationContent.SetValue("jobTitle", model.JobTitle);

I try with the above case not I can`t assign a selected value using surfacecontroller method in MVC.

Anyone have about then please give a solution so I can implement this case in my custom form.

Have only kicked the tires with U8, have you saved the new content? U7 - one of these?

_contentService.Save(registrationContent);
_contentService.SaveAndPublishWithStatus(registrationContent, 0, true);

Hi Guys,

For Umbraco 8 here is an example of my insert method also populating the dropdown field.

var content = _contentService.Create(reviewObject.Email, reviewObject.ParentId.Value, "umb8srReview");
                    if (content != null)
                    {
                        content.SetValue("firstName", reviewObject.FirstName);
                        content.SetValue("lastName", reviewObject.LastName);
                        content.SetValue("email", reviewObject.Email);

                        //###############
                        //THIS IS THE DROPDOWN FIELD
                        content.SetValue("rating", JsonConvert.SerializeObject(new[] { reviewObject.Rating }));
                        //###############

                        content.SetValue("review", reviewObject.Review);
                        content.SetValue("approved", reviewObject.Approved);
                        content.SetValue("reviewDate", reviewObject.ReviewDate);
                        content.SetValue("relatedId", reviewObject.RelatedId);
                        content.SetValue("memberId", reviewObject.MemberId);
                    }

                    _contentService.SaveAndPublish(content);

Simply wrap this around your value.

JsonConvert.SerializeObject(new[] { "your-value-here" })

Hope this helps someone.

Regards

David

Having a similar issue on Umbraco 10 essentially if a dropdown value is not set then I want to apply a default value which seems to be fine but not seeing the update value reflected in media section unless the page is refreshed:

 // If the reviewEvery property isn't set, set the default to "12 months"
                      SaveEventExtension.SetDropdownValues(media.Properties.FirstOrDefault(f => f.Alias == "reviewEvery"),
                            "Review Frequency", "12 months", _dts);

if (string.IsNullOrWhiteSpace(property?.GetValue()?.ToString()))
            {
                IDataType? preValueSource = dts.GetDataType(dataType);
                ValueListConfiguration? preValues = (ValueListConfiguration?)preValueSource?.Configuration;
                ValueListConfiguration.ValueListItem? listValue = preValues?.Items?.Find(item => item.Value == value);

                property?.SetValue(
                    JsonConvert.SerializeObject(new[]
                    {
                        listValue.Value
                    })
                );

            }

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