Swagger TypeError: Failed to execute ‘fetch’ on ‘Window’: Request with GET/HEAD method cannot have body

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I ran into this issue. Here is how I resolved it:

I had a method like this:

[HttpGet]
public IEnumerable<MyObject> Get(MyObject dto)
{
      ...
}

and I was getting the error. I believe swagger UI is interpreting the Get parameters as FromBody, so it uses the curl -d flag. I added the [FromQuery] decorator and the problem was resolved:

[HttpGet]
public IEnumerable<MyObject> Get([FromQuery]MyObject dto)
{
      ...
}

FYI this also changes the UI experience for that method. instead of supplying json, you will have a form field for each property of the parameter object.

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