标签:pen div nec ndt dynamic data name bpa 动态
利用SqlQuery实现动态查询
public static IEnumerable<dynamic> SqlQueryDynamic(this DbContext db, string Sql, params SqlParameter[] parameters)
{
using (var cmd = db.Database.Connection.CreateCommand())
{
cmd.CommandText = Sql;
if (cmd.Connection.State != ConnectionState.Open)
{
cmd.Connection.Open();
}
foreach (var p in parameters)
{
var dbParameter = cmd.CreateParameter();
dbParameter.DbType = p.DbType;
dbParameter.ParameterName = p.ParameterName;
dbParameter.Value = p.Value;
cmd.Parameters.Add(dbParameter);
}
using (var dataReader = cmd.ExecuteReader())
{
while (dataReader.Read())
{
var row = new ExpandoObject() as IDictionary<string, object>;
for (var fieldCount = 0; fieldCount < dataReader.FieldCount; fieldCount++)
{
row.Add(dataReader.GetName(fieldCount), dataReader[fieldCount]);
}
yield return row;
}
}
}
}
那么最终如上查询后返回动态集合,我们该如何转换为集合对象呢?我想都没想如下直接先序列化然后反序列化,若您有更好的解决方案,请自行实现即可。
using (var ctx = new EfDbContext())
{
ctx.Database.Log = Console.WriteLine;
var dynamicOrders = ctx.SqlQueryDynamic("select * from dbo.Orders");
var ordersJson = JsonConvert.SerializeObject(dynamicOrders);
var orders = JsonConvert.DeserializeObject<List<Order>>(ordersJson);
};
若有多个表也是好使的,最后反序列化为不同的对象即可
标签:pen div nec ndt dynamic data name bpa 动态
原文地址:https://www.cnblogs.com/tsql/p/9396244.html