Linq to SQL-运行时有多个where子句

Question

我正在尝试完成此操作，但是查询运行时仅使用我的第一个where子句。

对于.Net 3.5，这需要for，因此在4.0中的WhereIf不可用。

var query =
    from tb in dataContext.TableOne
    where tb.DateTimeCreated >= fromDate && 
        tb.DateTimeCreated <= toDate.AddDays(1) 
    select tb;

if (!string.IsNullOrEmpty(reference))
{
    query.Where(tb => tb.Reference = reference));
}

Answer 1

  if (!string.IsNullOrEmpty(reference))
        query = query.Where(tb => tb.Reference = reference));

Answer 2

尝试

只需做一个

var query = (from tb in dataContext.TableOne
                      where (tb.DateTimeCreated >= fromDate && tb.DateTimeCreated <= toDate.AddDays(1)) && (string.IsNullOrEmpty(reference) || tb.Reference == reference)
                      select tb
               );

或按照Ives所说：

query = query.Where(...)