从WebApi（post）返回多个值到AngularJs

Question

I am using .net core C#, WebApi & AngularJs.

For saving data my Angularjs code makes a $http call to my WebApi. I can return single data from my api fine but not sure whats the best method to return multiple values here. I can make it comma separated and then return as well, but wanted to know if there is a better approach to this.

So basically when the API saves data to my db, I want to return a variable, boolean value if the save was successful and an exception message in case the save was not successfully. Below is my code.

AngularJs Code:

service.saveData(data).then(function (res) {                          
    //get someDataToReturn, dataSaved & exception raised if any from db save here.
    }, function (err) {
});

WebApi Code:

[HttpPost("data/save")]
public async Task<IActionResult> SaveData([FromBody] List<UserData> data)
{
    bool dataSaved = true;
    string someDataToReturn = string.Empty;
    //do some processing and updating someDataToReturn here         

    //Saving data to DB
    dataSaved = SaveData(data);                

    //I want to return someDataToReturn, dataSaved(true or false) and exception raised from SaveData if any 
    return Ok(someDataToReturn);
}

//DB Call to save data
public bool SaveData(List<UserData> data)
{           
    try
    {
        foreach (var set in data)
        {
            //creating query etc

            _db.Execute(query);
        }                

        return true;
    }
    catch (SqlException ex)
    {

    }
    return false;
}

Let me know the best approach for this.

Answer 1

First of, you should check if the values in your request body is correctly populated.

Take a look at DataAnnotations . You can use annotations to specify which properties in your model that are Required, Min and Maxlength etc.

Here's an example on how to define a Name property to be required on the UserData class

public class UserData
{
    [Required]  
    public string Name { get; set; }        
}

If the request model do not fulfill the specified rules set on the UserData class DataAnnotations, the context ModelState will be set to false and contain the DataAnnotations errors. This can be used to determind if the current request is a bad request and return a proper http status code from that.

[HttpPost("data/save")]
public async Task<IActionResult> SaveData([FromBody] List<UserData> data)
{
    if (!ModelState.IsValid)
        return BadRequest(ModelState); //will return a 400 code
    ...

Then regarding the SaveData method. Capture the exception in the controller and return a proper status code from there

[HttpPost("data/save")]
public async Task<IActionResult> SaveData([FromBody] List<UserData> data)
{
    if (!ModelState.IsValid)
        return BadRequest(ModelState); //400 status code

    try
    {
        SaveData(data);
    }
    catch(Exception e)
    {
        return InternalServerError(e); //500 status code
    }

    string someDataToReturn = string.Empty;
    return Ok(someDataToReturn ); //200 status code
}

public void SaveData(List<UserData> data)
{           
    foreach (var set in data)
    {
        //creating query etc

       _db.Execute(query);
    }                
}

Answer 2

You can use the Controller class method Json(object data) . Something like:

[HttpPost("data/save")]
public async Task<IActionResult> SaveData([FromBody] List<UserData> data)
{
    return this.Json(SaveData(data));
}

See this .

Answer 3

you can create an entity and return it

public class BaseResult{
     public bool Result{get;set;}
     public string Errors{get;set;}
}

or only

return Ok( new { result = dataSaved , error= exception.Message});

Answer 4

the standard way is:
return 201 status code
https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/201

    [HttpPost("data/save")]
    public async Task<IHttpActionResult> SaveData([FromBody] List<UserData> data)
    {
        try
        {
            if (!ModelState.IsValid)
                return BadRequest(ModelState); 

            // return response of 201 if you created the resource successfully
            // typically return this with a uri to the new resource
            return Created("location", saveData(data));
        }
        catch (Exception)
        {
            return InternalServerError();
        }
    }