对于每个循环不循环 [英] For each loop not looping

问题描述

我正在尝试在运行时填充一些组合框。我在一个单独的模块中有这个代码，有其他形式调用这个子，所有工作正常。



当我运行代码的msg框的计数组合框返回6，但循环只运行一次??



感谢任何帮助。



< pre lang =vb> 公共 Sub PopulateCombos（myForm 正如表格）

Dim mySQL As 字符串 =
Dim myDispMember 作为 字符串
Dim myValue 作为 字符串
昏暗 x 作为 整数 = 0



' 调用SQL.Exceute查询 - 查询进入括号
' 遍历所有组合框

对于 每个 myCombo As ComboBox < span class =code-keyword>在 myForm.Controls.OfType（ of ComboBox）.ToArray

' 重置字符串
mySQL =
myDispMember =
myValue =

MsgBox（myForm.Name）
MsgBox（myCombo。名称）
MsgBox（myForm.Controls.OfType（ Of ComboBox）.Count（））
x = x + 1
MsgBox（x）

选择 案例 myCombo.Name.ToString

案例 cboClient ' 填充客户列表

mySQL = SELECT id，strSname，strFName FROM tblContacts
myDispMember = < span class =code-string> strSName
myValue = id

Case cboStatus ' < span class =code-comment>填充cboStatus

mySQL = SELECT id，strProjStatus FROM tblProjectStatus
myDispMember = strProjStatus
myValue = id


结束 选择

SQL.ExecQuery（mySQL）

< span class =code-keyword>如果 SQL.SQLDS.Tables.Count> 0 然后

带 myCombo

.DisplayMember = myDispMember
.ValueMember = myValue
.DataSource = SQL.SQLDS.Tables（ 0 ）
.AutoCompleteMode = AutoCompleteMode.SuggestAppend
.AutoCompleteSource = AutoCompleteSource.ListItems

End 使用

结束 如果



下一步 i

结束 Sub

解决方案

除了Next i （为什么？！）：你可能没有这种类型的任何控制 表格。这些控件很少直接放在表单上，​​更典型的是，它们作为一些嵌套面板和其他容器控件（例如标签页）的子项放置。你需要在一个单独的函数中抽象出循环，并在其实现中 递归地 调用它。



< DD> -SA

I am trying to populate some combo boxes at run time. I have this code in a separate module, there are other forms that call this sub and all work fine.

When I run the code the msg box for the count of combo boxes returns 6 but the loop only runs once??

Any help gratefully received.

Public Sub PopulateCombos(myForm As Form)

        Dim mySQL As String = ""
        Dim myDispMember As String
        Dim myValue As String
        Dim x As Integer = 0



        'Call the SQL.Exceute query - query goes in the the parentheses
        'loop through all the combo boxes

        For Each myCombo As ComboBox In myForm.Controls.OfType(Of ComboBox).ToArray

            'reset the strings
            mySQL = ""
            myDispMember = ""
            myValue = ""

            MsgBox(myForm.Name)
            MsgBox(myCombo.Name)
            MsgBox(myForm.Controls.OfType(Of ComboBox).Count())
            x = x + 1
            MsgBox(x)

            Select Case myCombo.Name.ToString

                Case "cboClient" 'populate client list

                    mySQL = "SELECT id, strSname, strFName FROM tblContacts"
                    myDispMember = "strSName"
                    myValue = "id"

                Case "cboStatus" 'Populate cboStatus

                    mySQL = "SELECT id, strProjStatus FROM tblProjectStatus"
                    myDispMember = "strProjStatus"
                    myValue = "id"

               
            End Select

            SQL.ExecQuery(mySQL)

            If SQL.SQLDS.Tables.Count > 0 Then

                With myCombo

                    .DisplayMember = myDispMember
                    .ValueMember = myValue
                    .DataSource = SQL.SQLDS.Tables(0)
                    .AutoCompleteMode = AutoCompleteMode.SuggestAppend
                    .AutoCompleteSource = AutoCompleteSource.ListItems

                End With

            End If



        Next i

    End Sub

解决方案

In addition to "Next i" (why?!): you may not have any controls of this type of the form. Such controls are rarely put on a form directly, more typically, they are put as children of some nested panels and other container controls (tab pages, for example). You need to abstract out the loop in a separate function and recursively call it in its implementation.

—SA

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