/// <summary>
/// 普通SELECT语句取多少记录(用替代法替换)
/// </summary>
/// <param name="connInfo"></param>
/// <param name="sql"></param>
/// <param name="param"></param>
/// <returns></returns>
public static int Count(this DbContext connInfo, string sql, object param)
{
bool useRepl = sql.StartsWith("SELECT", StringComparison.OrdinalIgnoreCase) &&
sql.IndexOf("UNION", StringComparison.OrdinalIgnoreCase) < 0;
if (useRepl)
{
if (!sql.StartsWith("SELECT COUNT(*)", StringComparison.OrdinalIgnoreCase))
{
int indexFROM = sql.IndexOf("FROM", 0, StringComparison.OrdinalIgnoreCase);
int indexORDERBY = sql.IndexOf("ORDER BY", 0, StringComparison.OrdinalIgnoreCase);
StringBuilder sqlbld = new StringBuilder(512);
sqlbld.Append("SELECT COUNT(*) ");
if (0 <= indexORDERBY)
{
sqlbld.Append(sql.Substring(indexFROM, indexORDERBY - indexFROM));
}
else
{
sqlbld.Append(sql.Substring(indexFROM));
}
return(SmartCrudHelper.GetIntValue(connInfo.ExecuteScalar(sqlbld.ToString(), param)));
}
return(connInfo.ExecuteScalar <int>(sql, param));
}
else
{
IDataReader reader = null;
try
{
reader = connInfo.ExecuteReader(sql, param);
int rows = 0;
while (reader.Read())
{
++rows;
}
return(rows);
}
finally
{
if (null != reader)
{
reader.Close();
}
}
}
}
public IDataReader GetReader()
{
return(_connInfo.ExecuteReader(GetSql(), param, cmdType: _CmdType));
}