/// <summary>
/// 异步执行没有结果的查询
/// </summary>
/// <param name="query">要执行的查询对象</param>
/// <param name="token">取消指示</param>
/// <returns>查询所影响的行数</returns>
public static async Task <int> ExecuteNonQueryAsync(this IDbExecutableQuery query, CancellationToken token = default(CancellationToken))
{
using (var context = await query.ExecuteAsync(token))
{
return(context.DataReader.RecordsAffected);
}
}
/// <summary>
/// 异步执行查询并将第一个结果集包装成 DataTable 返回
/// </summary>
/// <param name="query">要执行的查询对象</param>
/// <param name="token">取消指示</param>
/// <returns>查询结果</returns>
public static async Task <DataTable> ExecuteDataTableAsync(this IDbExecutableQuery query, CancellationToken token = default(CancellationToken))
{
using (var context = await query.ExecuteAsync(token))
{
var data = new DataTable();
data.Load(context.DataReader);
return(data);
}
}
/// <summary>
/// 异步执行查询并返回首行首列
/// </summary>
/// <param name="query">要执行的查询对象</param>
/// <param name="token">取消指示</param>
/// <returns>查询结果</returns>
public static async Task <object> ExecuteScalarAsync(this IDbExecutableQuery query, CancellationToken token = default(CancellationToken))
{
using (var context = await query.ExecuteAsync(token))
{
if (context.DataReader.Read())
{
return(context.DataReader[0]);
}
else
{
return(null);
}
}
}
/// <summary>
/// 异步执行查询并将所有结果集包装成 DataTable 返回
/// </summary>
/// <param name="query">要执行的查询对象</param>
/// <param name="token">取消指示</param>
/// <returns>查询结果</returns>
public static async Task <DataTable[]> ExecuteAllDataTablesAsync(this IDbExecutableQuery query, CancellationToken token = default(CancellationToken))
{
List <DataTable> dataTables = new List <DataTable>();
using (var context = await query.ExecuteAsync(token))
{
do
{
var data = new DataTable();
data.Load(context.DataReader);
dataTables.Add(data);
} while (context.DataReader.NextResult());
}
return(dataTables.ToArray());
}