我如何使用 COUNT 编写 LINQ to SQL?
示例:
var purch = from purchase in myBlaContext.purchases
select purchase;
这里怎样才能得到计数?
就像那样
var purchCount = (from purchase in myBlaContext.purchases select purchase).Count();
甚至更容易
var purchCount = myBlaContext.purchases.Count();
你应该能够对变量“purch”进行计数:
purch.Count();
例如。var purch = from purchase in myBlaContext.purchases
select purchase;
purch.Count();
lblCount.Text = myBlaContext.purchases.Count().ToString()
@Bside:lblCount.Text = myBlaContext.purchases.Count().ToString()
- George DuckettmyBlaContext.purchases.Count()
和(from purchase in myBlaContext.purchases select purchase.ID).Count()
,是否存在性能差异? - Raghuveer