using Newtonsoft.Json;

private void button1_Click(object sender, EventArgs e)

{

　　//序列化Json

　　string sql = "SELECT s.BusinessEntityID,s.Name FROM Sales.Store AS s";

　　textBox1.Text = JsonConvert.SerializeObject(DbHelper.GetDataTable(sql));

　　//反序列化Json

　　DataTable dt = new DataTable();

　　dt = JsonConvert.DeserializeObject<DataTable>(textBox1.Text);

　　dataGridView1.DataSource = dt;

}

private void button1_Click(object sender, EventArgs e)

{

　　//序列化Json

　　string sql = "SELECT s.BusinessEntityID,s.Name FROM Sales.Store AS s";

　　Task<string> task = new Task<string>(() => JsonConvert.SerializeObject(DbHelper.GetDataTable(sql)));

　　task.Start();
　　task.Wait();

　　textBox1.Text = task.Result;

　　//反序列化Json

　　DataTable dt = new DataTable();

　　string json = textBox1.Text;

　　Task<DataTable> dtTask = new Task<DataTable>(() => JsonConvert.DeserializeObject<DataTable>(json));

　　dtTask.Start();
　　dtTask.Wait();
　　dataGridView1.DataSource = dtTask.Result; 
}