Question

我在vb.net项目中有一个数据表，它是从存储过程填充的， dataTable中的数据如下所示：

Division        Department              Unit            ID
----------      ----------              ----------      -----
Division a      Business                Development     User 1              
Division a      Business                Development     User 1              
Division a      Business                Development     User 1              
Division a      Business                Development     User 1              
Division a      Business                Development     User 1              
Division a      Business                Development     User 1              
Division a      Business                Development     User 1              
Division a      Business                Development     User 1              
Division a      Business                Development     User 1              
Division a      Business                Development     User 1              
Division a      Business                Development     User 1              
Division a      Business                Management      User 2              
Division a      Business                Management      User 2              
Division a      Business                Management      User 2              
Division a      Business                Management      User 2              
Division a      Business                Management      User 2              
Division a      Business                Management      User 2              
Division a      Business                Management      User 2              
Division a      Business                Management      User 2              
Division a      Business                Management      User 2              
Division a      Business                Management      User 2              
Division a      Business Operations     Office Support  User 3                  
Division a      Business Operations     Office Support  User 3                  
Division a      Business Operations     Office Support  User 3

我想计算我拥有多少单位的数量，以及它的出现次数

例子：这里我有3个单位，（11个开发，10个管理和3个办公室支持）

Answer 1

轻松Linq-To-DataTable：

Dim unitGroups = From row In table.AsEnumerable()
                 Group row By unit = row.Field(Of String)("Unit") Into Group
                 Select unit = New With {.Name = unit, .Count = Group.Count()}
                 Order By unit.Count Descending
For Each grp In unitGroups
    Console.WriteLine("Unit: {0}  Count:{1}", grp.Name, grp.Count)
Next

不需要Order By，无论如何我想展示它。如果您想知道您需要的单位数量：

Dim countUnits As Int32 = unitGroups.Count()

Answer 2

一种可能的解决方法是这样做：

db

dt是你的数据表

从数据表中获取一些数据的计数

2 个答案: