PUT request to API is setting values to NULL

Question

I have this .Net Core API controller below that does a PUT request.

The table affected in Sql Server, looks like this:

carID  (varchar(15), NULL)
optionID (varchar(15), NOT NULL)
optionDescription (varchar(255), NULL)
optionType (varchar(50), NULL)
factoryID (varchar(15), NULL)

In testing, I am sending along the properties I want changed like this in my PUT API call:

{
    " optionID": "633fr",
    "optionDescription": "Full Tech Package A"
}

It does update the entry in the database, but it's also setting all the values not sent in the PUT call to NULL. So while it does update optionDescription, it is setting all the other values to NULL except optionID.

How do I stop it from setting the other values?

thanks!

Here is the controller:

    // PUT: api/CarOptions/5
    [HttpPut("{id}")]
    public async Task<IActionResult> PutCarOptions(Guid id, CarOptions carOptions)
    {
        if (id != carOptions.OptionId)
        {
            return BadRequest();
        }

        _context.Entry(carOptions).State = EntityState.Modified;

        try
        {
            await _context.SaveChangesAsync();
        }
        catch (DbUpdateConcurrencyException)
        {
            if (!CarOptionsExists(id))
            {
                return NotFound();
            }
            else
            {
                throw;
            }
        }

        return NoContent();
    }

Get the record from database, modify only the fields you want to, save to database? — Sami Kuhmonen
– Sami Kuhmonen, Commented Oct 9, 2020 at 14:39

Brando Zhang · Accepted Answer · 2020-10-12 06:03:03Z

1

According to your description, I suggest you could try to attach the model firstly and then set the specific property IsModified to true.

This will only update specific fields instead of updating whole model.

More details, you could refer to below example:

    // PUT: api/CarOptions/5
    [HttpPut("{id}")]
    public async Task<IActionResult> PutCarOptions(Guid id, CarOptions carOptions)
    {
        _context.Documents.Attach(carOptions);
        _context.Entry(carOptions).Property(x => x.optionDescription).IsModified = true;
        _context.SaveChanges();


        return NoContent();
    }

answered Oct 12, 2020 at 6:03

Brando Zhang

29.1k6 gold badges42 silver badges71 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

PUT request to API is setting values to NULL

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related