Question

我有一个搜索页面，其中包含一系列3个下拉菜单，用户可以使用这些下拉菜单来限制搜索结果。每个下拉列表的初始值为ALL。如果任何值具有除ALL之外的值，则需要将其包含在WHERE语句中。

这是我陷入困境的地方。我的Linq Select是......

Dim myComponents = From searchComponents In dc.Components _
                   Where searchComponents.Type = ddl_Type.SelectedValue _
                   AndAlso searchComponents.Size = ddl_Size.SelectedValue _
                   AndAlso searchComponents.WR = ddl_WR.SelectedValue _
                   Select searchCompnents)

目前我的搜索将包含所有ddl selectedValues。我需要删除任何值为ALL的东西。我希望我已经正确解释了。示例如果ddl_Size.SelectedValue = "ALL"那么我的陈述将是......

Dim myComponents = From searchComponents In dc.Components _
                       Where searchComponents.Type = ddl_Type.SelectedValue _
                       AndAlso searchComponents.WR = ddl_WR.SelectedValue _
                       Select searchCompnents)

如何在代码中实现此目的。感谢

Answer 1

Dim myComponents = From searchComponents In dc.Components _
                   Where   (ddl_Type.SelectedValue = "ALL" OrElse searchComponents.Type = ddl_Type.SelectedValue) _
                   AndAlso (ddl_Size.SelectedValue = "ALL" OrElse searchComponents.Size = ddl_Size.SelectedValue) _
                   AndAlso (ddl_WR.SelectedValue = "ALL" OrElse searchComponents.WR = ddl_WR.SelectedValue) _
                   Select searchCompnents)

Linq选择基于下拉值的位置

1 个答案: