Blazor服务器项目

Question

我是C#的新手。试图在Blazor服务器项目中调用rest api时，我得到了以下错误：JsonException："<"是一个值的无效开头。路径：$|行号：1|BytePositionInLine:0。

我的服务：

public class EmployeeService : IEmployeeService
{
private readonly HttpClient httpClient;
public EmployeeService(HttpClient httpClient)
{
this.httpClient = httpClient;
}
public async Task<IEnumerable<Employee>> GetEmployees()
{
return await httpClient.GetJsonAsync<Employee[]>("api/employees");

}
}

我的控制器：

[Route("/api/[controller]")]
[ApiController]

public class EmployeesController : ControllerBase
{
private readonly IEmployeeRepository employeeRepository;
//EmployeeRepository objemployee = new EmployeeRepository();
public EmployeesController(IEmployeeRepository employeeRepository)
{
this.employeeRepository = employeeRepository;
}
[HttpGet]
public async Task<ActionResult> GetEmployees()
{
try
{
return Ok(await employeeRepository.GetEmployees());
}
catch (Exception)
{
return StatusCode(StatusCodes.Status500InternalServerError, "Error retrieving data from DB");
}
}
}

Answer 1

在EmployeeService中尝试这样的操作，它将有助于了解调试时出现的问题。您可以先检查response.ReasonPhrase。

public async Task<IEnumerable<Employee>> GetEmployees()
{
var response = await httpClient.GetAsync("api/employees");
if (response.IsSuccessStatusCode)
{
var result = await JsonSerializer.DeserializeAsync<Employee[]>(await response.Content.ReadAsStreamAsync(), new JsonSerializerOptions() { PropertyNameCaseInsensitive = true });
return result;
}
else
{
//handle the response that was not successful here.
}
}