vb.net 数组到组合框？

Array to combo box?

提问by mossypne

I have this structure, with an array of the structure type.

我有这个结构，带有结构类型的数组。

Structure CustomerAccountsRec
    Dim strFirstName As String
    Dim strLastName As String
    Dim intAge As Integer
    Dim strAddress As String
    Dim strTown As String
    Dim strPostcode As String
    Dim strCusNum As String
End Structure

Public strCusArray() As CustomerAccountsRec

I want to be able to take the strCusNum of the array and populate a combobox with it but can't figure out how. Any help?

我希望能够获取数组的 strCusNum 并用它填充一个组合框，但无法弄清楚如何。有什么帮助吗？

回答by Mark Hall

You can also override the ToStringMethod in your Structure as mentioned. I also created a List(Of CustomerAccountsRec)that makes it a bit easier to add values and then I bound the list to the ComboBox'sDataSource

ToString如上所述，您还可以覆盖结构中的方法。我还创建了一个List(Of CustomerAccountsRec)使添加值更容易的方法，然后我将列表绑定到ComboBox's数据源

Public Class Form1
    Structure CustomerAccountsRec
        Dim strFirstName As String
        Dim strLastName As String
        Dim intAge As Integer
        Dim strAddress As String
        Dim strTown As String
        Dim strPostcode As String
        Dim strCusNum As String
        Public Overrides Function ToString() As String
            Return strCusNum
        End Function
    End Structure

    Public strCusArray As List(Of CustomerAccountsRec) = New List(Of CustomerAccountsRec)

    Public Sub New()

        ' This call is required by the designer.
        InitializeComponent()

        ' Add any initialization after the InitializeComponent() call.

        Dim carec As CustomerAccountsRec = New CustomerAccountsRec
        carec.strFirstName = "Hello"
        carec.strLastName = "World"
        carec.strCusNum = "Hello World"
        carec.strTown = "AnyTown"
        carec.strAddress = "AnyStreet"
        carec.strCusNum = "12345678"
        strCusArray.Add(carec)
        ComboBox1.DataSource = strCusArray

    End Sub
End Class

回答by spajce

If I understand your question.

如果我理解你的问题。

The actual result of Public strCusArray() As CustomerAccountsRecis null, so we can't use this to add the all items from CustomerAccountsRecto ComboBox

的实际结果Public strCusArray() As CustomerAccountsRec是空的，所以我们不能用它来添加从CustomerAccountsRec到 的所有项目ComboBox

To Listall the item from your Structurewe need to use the System.Reflection Namespace

对于您的List所有项目，Structure我们需要使用System.Reflection 命名空间

  Structure CustomerAccountsRec
        Dim strFirstName As String
        Dim strLastName As String
        Dim intAge As Integer
        Dim strAddress As String
        Dim strTown As String
        Dim strPostcode As String
        Dim strCusNum As String
  End Structure

  Dim fi As FieldInfo() = GetType(CustomerAccountsRec).GetFields(BindingFlags.[Public] Or BindingFlags.Instance)
        For Each info As FieldInfo In fi
            ComboBox2.Items.Add(info.Name)
  Next

Source: C# version

来源：C# 版本

回答by omittones

You can add the items using the ComboBox.Items.Add method, and for the structure to be properly displayed, you have to override it's ToString method.

您可以使用 ComboBox.Items.Add 方法添加项目，为了正确显示结构，您必须覆盖它的 ToString 方法。

See:

看：

ComboBox: Adding Text and Value to an Item (no Binding Source)

ComboBox：向项目添加文本和值（无绑定源）

how to add value to combobox item

如何为组合框项添加值

回答by Jason Tyler

You can use LINQ to get an array containing the items you want to display, and then bind that array to the ComboBox.

您可以使用 LINQ 获取包含要显示的项目的数组，然后将该数组绑定到ComboBox.

Dim combo as New ComboBox
combo.DataSource = strCusArray.Select(Function(f) f.strCusNum).ToArray()