/// <summary>
/// 根据标识列的值返回整条数据
/// </summary>
/// <param name="IdentityValue">标识列的值</param>
/// <returns></returns>
internal DataTable SelectByIdentity(string IdentityValue)
{
string strTable = "";
string strCondition = "";
try
{
//获取表名
strTable = InternalBase <T> .GetTableName();
//获取条件
PropertyInfo[] pi = typeof(T).GetProperties();
foreach (var item in pi)
{
var temp = InternalBase <T> .GetColumnAttribute(item);
if (temp.Identity)
{
strCondition = item.Name + "='" + IdentityValue + "'";
break;
}
}
string sql = string.Format("select * from {0} where {1}", strTable, strCondition);
return(dbl.ExecuteQuery(sql));
}
catch (Exception ex)
{
LogHelper.WriteLog(ex);
return(null);
}
}
/// <summary>
/// 查询返回所有数据,根据字典生成条件,用于时间条件为时间段时.
/// </summary>
/// <param name="dic">保存条件的字典,key为字段名称,关键字:数据库字段名__q(时间起),数据库字段名__z(时间止),数据库字段名__or(条件为or),数据库字段名__like(查询为like)</param>
/// <param name="order">排序字段:如果不需要排序可不传入数据,也可以传入null或者"";如果需要排序则写入order by之后的内容</param>
/// <param name="tableName">表名</param>
/// <param name="columnName">列名,默认为*,查询所有</param>
/// <returns></returns>
public DataTable Select(Dictionary <string, object> dic, string order = "", string tableName = "", string columnName = "*")
{
string sql = string.Empty;
try
{
string strTable = InternalBase <T> .GetTableName(tableName);
string strCondition = InternalBase <T> .GetConditionByDIC(dic);
string strOrder = InternalBase <T> .AddOrder(order);//获取排序字段
sql = string.Format("select {0} from {1} {2} {3}", columnName, strTable, strCondition, strOrder);
return(dbl.ExecuteQuery(sql));
}
catch (Exception ex)
{
LogHelper.WriteLog(ex, sql);
return(null);
}
}
/// <summary>
/// 查询返回所有数据,根据实体对象生成条件.
/// </summary>
/// <param name="t">实体类,将查询条件赋给实体类的属性</param>
/// <param name="order">排序字段:如果不需要排序可不传入数据,也可以传入null或者"";如果需要排序则写入order by之后的内容</param>
/// <param name="columnName">列名,默认为*,查询所有</param>
/// <returns></returns>
public DataTable Select(T t, string order = "", string columnName = "*")
{
string sql = string.Empty;
try
{
string strTable = InternalBase <T> .GetTableName();
string strCondition = InternalBase <T> .GetParamForSelectAndDelete(t);
string strOrder = InternalBase <T> .AddOrder(order);//获取排序字段
sql = string.Format("select {0} from {1} {2} {3}", columnName, strTable, strCondition, strOrder);
return(dbl.ExecuteQuery(sql));
}
catch (Exception ex)
{
LogHelper.WriteLog(ex, sql);
return(null);
}
}
/// <summary>
/// 根据sql语句进行查询,返回唯一的字符串
/// </summary>
/// <param name="sql">查询语句</param>
/// <returns></returns>
public string GetOnlyColumnValue(string sql)
{
DataBaseLayer dbl = new DataBaseLayer();
DataTable dt = dbl.ExecuteQuery(sql);
if (dt.Rows.Count > 0)
{
return(dt.Rows[0][0].ToString());
}
else
{
return("");
}
}
/// <summary>
/// 根据sql语句进行查询,返回数据
/// </summary>
/// <param name="sql">sql语句</param>
/// <returns></returns>
public DataTable SelectBySQL(string sql)
{
return(dbl.ExecuteQuery(sql));
}