在ASP.Net Core 2.2中，复杂对象以NULL的形式出现在HttpPut中

Question

I am building a webapi using Asp.Net Core 2.2. One of my controllers has a Put method to update an entity. The problem is, the complex object I pass from postman rest client is always null.

[HttpPut]
[Route("{searchPatternId:long}")]
public async Task<IActionResult> Put(long searchPatternId, [FromBody]SearchPattern searchPattern)
{
        try
        {
            if (searchPattern == null) return BadRequest();

            return Ok(await _searchPatternService.PutAsync(searchPattern));
        }
        catch (Exception e)
        {
            await _errorLogService.Log(e);
            return StatusCode(500);
        }
}

SearchPattern class:

[Table("search_pattern", Schema = "abc")]
public class SearchPattern
{
    [Key]
    public long SearchPatternId { get; set; }
    public string Pattern { get; set; }
    public long PatternHash { get; set; }
    public int? Age { get; set; }
    public string Location { get; set; }
    public long TotalRecordsFound { get; set; }
    public int TotalPages { get; set; }
    public int LastSearchedPage { get; set; }
    public string MachineName { get; set; }
    public string CreatedBy { get; set; }
    public DateTime CreatedDate { get; set; }
    public string UpdatedBy { get; set; }
    public DateTime? UpdatedDate { get; set; }
    public string Url { get; set; }
}

Postman request:

This is what I have tried so far:

[HttpPut]
[Route("{searchPatternId:long}")]
public async Task<IActionResult> Put([FromRoute]long searchPatternId, [FromBody]SearchPattern searchPattern)

[HttpPut("{searchPatternId:long}")]    
public async Task<IActionResult> Put([FromRoute]long searchPatternId, [FromBody]SearchPattern searchPattern)

[HttpPut]
public async Task<IActionResult> Put([FromBody]SearchPattern searchPattern)

Debugging Output:

Answer 1

The searchPattern parameter is set to null because model binder got at least one invalid value for model property. In your case it's obvious that updateDate is mapped to DateTime type but specified value has invalid format

2019-03-27T01:20:00 PM

PM part is invalid here, just remove it

2019-03-27T01:20:00

Also make sure all other fields have valid values to fix your problem.