/// <summary>
/// 获取一个LinqDLRColumn的新实例
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="columnexpress"></param>
/// <param name="belongto"></param>
/// <param name="sqlflags"></param>
/// <returns></returns>
public static T New <T>(string columnexpress, LamdaSQLObject <T> belongto, SqlOperatorFlags sqlflags) where T : LinqDLRColumn
{
T t = (T)Activator.CreateInstance(typeof(T), true);
t.ColumnExpress = columnexpress;
t.BelongToObject = belongto;
t.ConditionValues = new Dictionary <string, object>();
t.SqlFlags = sqlflags;
return(t);
}
/// <summary>
/// 生成一个对象的的栏位表达式
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="value"></param>
/// <param name="sqlflags"></param>
/// <returns></returns>
public static LinqDLRColumn New <T>(object value, SqlOperatorFlags sqlflags) where T : LinqDLRColumn
{
if (value is LinqDLRColumn)
{
return((LinqDLRColumn)value);
}
LinqDLRColumn t = (LinqDLRColumn)Activator.CreateInstance(typeof(T), true);
t.ConditionValues = new Dictionary <string, object>();
t.ColumnExpress = t.Convert2Express(value);
t.SqlFlags = sqlflags;
return(t);
}
/// <summary>
/// 构建Lamda表达式对象
/// </summary>
/// <param name="table"></param>
/// <param name="sqlflags"></param>
public LamdaSQLObject(string table, SqlOperatorFlags sqlflags)
{
BelongToTable = table;
SqlFlags = sqlflags;
}
/// <summary>
/// 生成一个LinqDLRTable的实例
/// </summary>
/// <param name="table">实际table的名称</param>
/// <param name="aliasName">table的别名</param>
/// <param name="sqlflags">sql相关操作符号</param>
/// <returns>LinqDLRTable</returns>
public static LinqDLRTable New <TColumn>(string table, string aliasName = "", SqlOperatorFlags sqlflags = null) where TColumn : LinqDLRColumn
{
var tn = aliasName == "" ? table : aliasName;
sqlflags = sqlflags == null ? new SqlOperatorFlags() : sqlflags;
LinqDLRTable rtn = New <LinqDLRTable>(new LamdaSQLObject <TColumn>(tn, sqlflags), table, aliasName, new GeneralLinqDLR2SQLGenerator(sqlflags));
return(rtn);
}
/// <summary>
/// 获取一个LinqDLRColumn的新实例
/// </summary>
/// <param name="dlrcolumntype"></param>
/// <param name="columnexpress"></param>
/// <param name="belongto"></param>
/// <param name="sqlflags"></param>
/// <returns></returns>
protected static LinqDLRColumn New(Type dlrcolumntype, string columnexpress, object belongto, SqlOperatorFlags sqlflags)
{
LinqDLRColumn t = (LinqDLRColumn)Activator.CreateInstance(dlrcolumntype, true);
t.ColumnExpress = columnexpress;
t.BelongToObject = belongto;
t.ConditionValues = new Dictionary <string, object>();
t.SqlFlags = sqlflags;
return(t);
}
