组合框选定项与其选定项不匹配

Question

我遇到了在字母完成后出现空格超过 Combobox.SelectedItem 长度的问题。为什么？我该如何解决这个问题？

下面是我的问题，它是一个非常短小的视频。 Here is a small video

Imports System.Data.SqlClient
Public Class Main
WithEvents bsData As New BindingSource
Dim sConn As New SqlConnection
Dim dt As New DataTable
Dim ds As New DataSet
Private Sub Main_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    sConn.ConnectionString = "Data Source=PC-N39;Initial Catalog=Esi01;Persist    Security Info=True;User ID=sa;Password=sas"
    sConn.Open()
    Try
        Dim myTable As DataTable = New DataTable("MyTable")
        myTable.Columns.Add(New DataColumn("Group Code"))
        myTable.Columns.Add(New DataColumn("Description"))
        myTable.Columns.Add(New DataColumn("NothingSerious"))
        Dim cmd As New SqlCommand("Select * from tbUnit", sConn)
        Dim dr As SqlDataReader = cmd.ExecuteReader(CommandBehavior.Default)
        Dim myRow As DataRow
        While dr.Read()
            myRow = myTable.NewRow
            myRow.Item(0) = dr(0)
            myRow.Item(1) = dr(1)
            myRow.Item(2) = dr(2)
            myTable.Rows.Add(myRow)
        End While
        dr.Close()
        Dim myData4 As DataTable = myTable
        ds = New DataSet()
        ds.Tables.Add(myData4)
        MultiColumnCombo1.DisplayMember = "Group Code"
        MultiColumnCombo1.DrawMode = DrawMode.OwnerDrawVariable
        MultiColumnCombo1.ColumnWidths = "50;150"
        MultiColumnCombo1.DataSource = myData4
        MultiColumnCombo1.Text = String.Empty
    Catch ex As Exception
        MsgBox(ex.ToString)
    End Try
    sConn.Close()
End Sub
End Class

Answer 1

MultiColumnCombo1 是什么类型？我想这是第三方组件。 据我在您的视频中看到的，它似乎占用了数据中最大的元素，取其长度并为其他元素添加空格以使其大小相同。

您可能无法更改组件的行为，但您可以将相同的逻辑应用于您在 TextBox 中输入的内容：添加空格以使它们匹配。或者，如果您只需要创建一个条件来测试它们是否相等，您可以执行以下操作：

if(YourComboboxSelectedItem.Trim() == StringYourAreComparingItTo)

请参阅String.Trim()，这将丢弃多余的空格。