我创建了测试控制台应用程序(使用 net core3.0),代码如下:
using System;
using System.IO;
using System.Text.Json;
using System.Threading.Tasks;
namespace TestConsoleApp1
{
class Program
{
async static Task Main(string[] args)
{
var obj = new { Name = "Test", Age = 18 };
string json = string.Empty;
using (var stream = new MemoryStream())
{
await JsonSerializer.SerializeAsync(stream, obj);
stream.Position = 0;
using var reader = new StreamReader(stream);
json = await reader.ReadToEndAsync();
}
Console.WriteLine(json); //output {"Name":"Test","Age":18}, is ok
Console.WriteLine(await GetJson(obj)); //output {}, why?
Console.ReadLine();
}
private static async Task<string> GetJson(object obj)
{
string json = string.Empty;
using (var stream = new MemoryStream())
{
await JsonSerializer.SerializeAsync(stream, obj);
stream.Position = 0;
using var reader = new StreamReader(stream);
json = await reader.ReadToEndAsync();
}
return json;
}
}
}
运行输出
{"Name":"Test","Age":18} //ok
{} //为什么?
相同的代码,但输出不同的结果,为什么?