利用反射将Datatable、SqlDataReader转换成List模型
1. DataTable转IList
public class DataTableToList<T>whereT :new()
{
///<summary>
///利用反射将Datatable转换成List模型
///</summary>
///<param name="dt"></param>
///<returns></returns>
public static List<T> ConvertToList(DataTabledt)
{
List<T> list =newList<T>();
Typetype =typeof(T);
stringtempName =string.Empty;
foreach(DataRowdrindt.Rows)
{
T t =newT();
PropertyInfo[] propertys =
t.GetType().GetProperties();
foreach(PropertyInfopiinpropertys)
{
tempName = pi.Name;
if(dt.Columns.Contains(tempName))
{
if(!pi.CanWrite)
{
continue;
}
var value = dr[tempName];
if(value !=DBNull.Value)
{
pi.SetValue(t, value,null);
}
}
}
list.Add(t);
}
returnlist;
}
}
2. SqlDataReader转IList
/// <summary>
/// 判断SqlDataReader是否存在某列
/// </summary>
/// <param name="dr">SqlDataReader</param>
/// <param name="columnName">列名</param>
/// <returns></returns>
private bool readerExists(SqlDataReader dr, string columnName)
{
dr.GetSchemaTable().DefaultView.RowFilter = "ColumnName= '" + columnName + "'";
return (dr.GetSchemaTable().DefaultView.Count > 0);
}
///<summary>
///利用反射和泛型将SqlDataReader转换成List模型
///</summary>
///<param name="sql">查询sql语句</param>
///<returns></returns>
public IList<T> ExecuteToList<T>(string sql) where T : new()
{
IList<T> list;
Type type = typeof (T);
string tempName = string.Empty;
using (SqlDataReader reader = ExecuteReader(sql))
{
if (reader.HasRows)
{
list = new List<T>();
while (reader.Read())
{
T t = new T();
PropertyInfo[] propertys = t.GetType().GetProperties();
foreach (PropertyInfo pi in propertys)
{
tempName = pi.Name;
if (readerExists(reader, tempName))
{
if (!pi.CanWrite)
{
continue;
}
var value = reader[tempName];
if (value != DBNull.Value)
{
pi.SetValue(t, value, null);
}
}
}
list.Add(t);
}
return list;
}
}
return null;
}
3、结果集从存储过程获取
/// <summary>
/// 处理存储过程
/// </summary>
/// <param name="spName">存储过程名</param>
/// <param name="parameters">参数数组</param>
/// <returns>sql数据流</returns>
protected virtual SqlDataReader ExecuteReaderSP(string spName, ArrayList parameters)
{
SqlDataReader result = null;
cmd.CommandText = spName;
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Clear();
if (parameters != null)
{
foreach (SqlParameter param in parameters)
{
cmd.Parameters.Add(param);
}
}
try
{
Open();
result = cmd.ExecuteReader(CommandBehavior.CloseConnection);
}
catch (Exception e)
{
if (result != null && (!result.IsClosed))
{
result.Close();
}
LogHelper.WriteLog("\r\n方法异常【ExecuteReaderSP(string spName, ArrayList parameters)】" + spName, e);
throw new Exception(e.Message);
}
return result;
}
///<summary>
///利用反射将SqlDataReader转换成List模型
///</summary>
///<param name="spName">存储过程名称</param>
///<returns></returns>
public IList<T> ExecuteQueryListSP<T>(string spName, params SqlParameter[] listParams) where T : new()
{
IList<T> list;
Type type = typeof(T);
string tempName = string.Empty;
using (SqlDataReader reader = ExecuteReaderSP(spName, new ArrayList(listParams)))
{
if (reader.HasRows)
{
list = new List<T>();
while (reader.Read())
{
T t = new T();
PropertyInfo[] propertys = t.GetType().GetProperties();
foreach (PropertyInfo pi in propertys)
{
tempName = pi.Name;
//for (int intField = 0; intField < reader.FieldCount; intField++)
//{//遍历该列名是否存在
//}
if (readerExists(reader, tempName))
{
if (!pi.CanWrite)
{
continue;
}
var value = reader[tempName];
if (value != DBNull.Value)
{
pi.SetValue(t, value, null);
}
}
}
list.Add(t);
}
return list;
}
}
return null;
}