最近学习Linq to SQL，发现Linq是一个开发轻量数据库的好东西，大大简化了数据连接、查询过程。但是在绑定ComBoBox的时间发现了一个问题：Linq查询后得到的数据tolist后，只能实现DataSource绑定，无法赋值DisplayMember和ValueMember，即使赋值后，SelectedValue也得不到想要的数值。例如：
Dim tempProvince = From cust In db.AddressProvince Select New With {.id = cust.ProvinceID, .name = cust.ProvinceName} cmbProvince.DataSource = tempProvince.tolist cmbProvince.DisplayMember = "name" cmbProvince.ValueMember = "id"
在网上搜索了几天，有说解决的办法是将List转换为DataTable，然后绑定，转换代码：
''' <summary> ''' List转换为DataTable ''' </summary> ''' <param name="list">List</param> ''' <returns>DataTable</returns> ''' <remarks></remarks> Public Function ConvertToDataTable(ByVal list As IList) As DataTable Dim table As New DataTable() Dim fields() As PropertyInfo If list.Count > 0 Then fields = list（0）.GetType.GetProperties For Each field In fields table.Columns.Add(field.Name, field.PropertyType) Next For Each item In list Dim row As DataRow = table.NewRow() For Each field In fields row(field.Name) = field.GetValue(item) Next table.Rows.Add(row) Next End If Return table End Function
绑定代码：
Dim tempProvince = From cust In db.AddressProvince Select New With {.id = cust.ProvinceID, .name = cust.ProvinceName} Dim tempdatatable As New DataTable tempdatatable = ConvertToDataTable(tempProvince.ToList) cmbProvince.DataSource = tempdatatable '绑定DataTable数据时引发SelectedIndexChanged事件
cmbProvince.DisplayMember = "name" cmbProvince.ValueMember = "id"
通过上述转换后，可以正确的绑定到ComBoBox了，但有出现了一个新问题，在绑定数据后引发了SelectedIndexChanged事件，ComBoBox的SelectedValue值还是错误的，代码：
Private Sub cmbProvince_SelectedIndexChanged(sender As Object, e As EventArgs) Handles cmbProvince.SelectedIndexChanged
Dim tempCity = From cust In db.AddressCity Where cust.ProvinceID = cmbProvince.SelectedValue.ToString
Select New With {.id = cust.CityID, .name = cust.CityName}
End Sub
郁闷了半天，灵机一动，更改后的绑定代码：
Dim tempProvince = From cust In db.AddressProvince Select New With {.id = cust.ProvinceID, .name = cust.ProvinceName} Dim tempdatatable As New DataTable tempdatatable = ConvertToDataTable(tempProvince.ToList)
cmbProvince.DisplayMember = "name" cmbProvince.ValueMember = "id"cmbProvince.DataSource = tempdatatable '重点：DataSource放到了DisplayMember和ValueMember赋值后。
哈哈，问题解决了！......
你以为这就结束了？
NO！
这不是重点，高潮来了：
心血来潮，把转换过程去掉了，直接绑定Linq查询结果：
Dim tempProvince = From cust In db.AddressProvince Select cust.ProvinceID, cust.ProvinceName cmbProvince.DisplayMember = "ProvinceName" cmbProvince.ValueMember = "ProvinceID" cmbProvince.DataSource = tempProvince
居然也正常运行了！！！
最后总结：
ComBoBox可以绑定Linq查询的结果，唯一的要求就将DataSource放在DisplayMember和ValueMember的后面。
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