C# 如何基于下拉值动态创建VB.NET控件

请提供任何有用的链接

我需要在VB.NET中创建一个示例问题类型web表单，允许用户执行以下操作：

用户从下拉列表中选择控件类型（文本框、单选按钮、列表框等）

根据Web窗体上的控件类型动态生成控件

它将始终显示文本框（用户在其中编写问题）和（生成的控件-文本框、单选按钮、列表框等），并将这些值保存到数据库中

在web表单上显示生成的示例问题

---

谢谢。

类似的东西应该可以工作（没有数据库交互；）

aspx：

控制工厂：

static class ControlFactory {
  public static Control Create(string type) {
    if ("TextBox".Equals(type))
      return new TextBox();

    if ("RadioButton".Equals(type)) 
      return new RadioButtonList();
  }
}

---

我认为您正在寻找的是一个DBMS解决方案，在该解决方案中，您可以在DB中保存控件的类型，而不是在需要显示页面时查看该类型并使用占位符生成所需内容。

---

这里有一个维基百科的链接，它解释了DBMS：

我使用声明性语法和数据绑定做了类似的事情

抱歉，代码太长了，但是只发布没有嵌套中继器的相关部分可能没有意义。我正在发布上下文的完整嵌套转发器代码

在我的设置中，这是一个调查应用程序，带有问题组（外部重复），由一个或多个问题组成（嵌套重复）

其工作原理的相关部分在代码示例中的嵌套中继器中。我在标记中有所有可用的控件，。但是每个的.Visible属性都是基于QuestionType设置的

    <asp:Repeater ID="Repeater1" runat="server">
        <ItemTemplate>
            <div class="questiongroup">
                <asp:HiddenField runat="server" ID="lblQuestionGroupId" Value='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "QuestionGroupId").ToString()) %>'>
                </asp:HiddenField>
                <asp:HiddenField runat="server" ID="hfSortOrder" Value='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "SortOrder").ToString()) %>'>
                </asp:HiddenField>
                <asp:HiddenField runat="server" ID="hdnPointsAwarded" Value='0'></asp:HiddenField>
                <br />
                <h3><asp:Label runat="server" ID="txtQuestionGroupName" MaxLength="50" Columns="50" Text='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "QuestionGroupName").ToString()) %>'></asp:Label>
                </h3>
                Score Section
                <asp:CheckBox runat="server" ID="chkIsScoreSection" Enabled="false" TabIndex="-1"
                    Checked='<%# Convert.ToBoolean(DataBinder.Eval(Container.DataItem, "IsScoreSection")) %>' />
                Minimum required correct answers:
                <asp:Label runat="server" ID="lblMinimumForScore" MaxLength="3" Columns="3" Text='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "CommentsRequiredMinimumYesAnswers").ToString()) %>'></asp:Label>
                  Point Value <asp:Label ID="lblPossiblePoints" runat="server" Text='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "PossiblePoints").ToString()) %>' />
                          <br />
                Group Instructions
                <br />
                <asp:Label runat="server" ID="lblGroupInstructions" TextMode="MultiLine" Columns="50" Rows="3"
                    Text='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "GroupInstructions").ToString()) %>'></asp:Label>
                <br />
                <div class='questionseditor'>
                </div>
                <br />
                <div class="questionsdiv">
                    <asp:Repeater ID="childRepeater" runat="server" DataSource='<%# ((DataRowView)Container.DataItem).Row.GetChildRows("Relation2") %>'>
                        <ItemTemplate>
                        <div class="question">
                            <asp:HiddenField ID="hdnQuestionType" runat="server" Value='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) %>' />
                            <asp:HiddenField ID="hdnQuestionId" runat="server" Value='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionId\"]").ToString()) %>' />
                            <asp:HiddenField ID="hfQuestionSortOrder" runat="server" Value='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"SortOrder\"]").ToString()) %>' />
                            <asp:RequiredFieldValidator SetFocusOnError="True" ID="YesNoForScoreRequiredFieldValidator" runat="server"
                                ControlToValidate="lstYesNoForScore" Display="Dynamic" ErrorMessage="Required<br />"
                                Enabled='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "1" %>'></asp:RequiredFieldValidator>
                            <asp:RequiredFieldValidator SetFocusOnError="True" ID="MemoRequiredFieldValidator" runat="server" ControlToValidate="txtMemoAnswer"
                                Display="Dynamic" ErrorMessage="Required<br />" 
                                Enabled='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "2" %>'></asp:RequiredFieldValidator>
                            <asp:RequiredFieldValidator SetFocusOnError="True" ID="NumericAnswerRequiredFieldValidator" runat="server"
                                ControlToValidate="txtNumericAnswer" Display="Dynamic" ErrorMessage="Required<br />"
                                Enabled='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "3" %>'></asp:RequiredFieldValidator>
                            <asp:RegularExpressionValidator SetFocusOnError="True" Display="Dynamic" runat="server" ID="NumericTextRegexValidator"
                                ValidationExpression="^\d*[0-9](|.\d*[0-9]|,\d*[0-9])?$" Enabled='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "3" %>'
                                ErrorMessage="*Invalid<br />" ControlToValidate="txtNumericAnswer"></asp:RegularExpressionValidator>
                            <asp:RequiredFieldValidator SetFocusOnError="True" ID="RequiredFieldValidator1" runat="server" ControlToValidate="lstYesNoNonScored"
                                Display="Dynamic" ErrorMessage="Required<br />" Enabled='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "5" %>'></asp:RequiredFieldValidator>
                            <asp:Label ID="lblQuestionText" runat="Server" Text='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionText\"]").ToString()) %>'></asp:Label><br />
                            <asp:RadioButtonList runat="server" ID="lstYesNoForScore" RepeatDirection="Horizontal"
                                Visible='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "1" %>'>
                                <asp:ListItem Text="Yes" Value="1"></asp:ListItem>
                                <asp:ListItem Text="No *" Value="0"></asp:ListItem>
                            </asp:RadioButtonList>
                            <asp:TextBox ID="txtMemoAnswer" runat="server" Visible='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "2" %>'
                                TextMode="MultiLine" Rows="3" Width="100%"></asp:TextBox>
                            <asp:TextBox ID="txtNumericAnswer" runat="server" Visible='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "3" %>'
                                cols="5"></asp:TextBox>
                            <uc1:MultipleChoiceControl ID="MultipleChoiceControl1" runat="server" Visible='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "4" %>'
                                QuestionId='<%# Convert.ToInt32(DataBinder.Eval(Container.DataItem, "[\"QuestionId\"]")) %>' />
                            <asp:RadioButtonList runat="server" ID="lstYesNoNonScored" RepeatDirection="Horizontal"
                                Visible='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "5" %>'>
                                <asp:ListItem Text="Yes" Value="1"></asp:ListItem>
                                <asp:ListItem Text="No" Value="0"></asp:ListItem>
                            </asp:RadioButtonList>
                            <br />
                            </div>
                        </ItemTemplate>
                    </asp:Repeater>
                </div>
                Comments for this Question Group (Required if score not awarded)
                <asp:TextBox ID="txtGroupComments" runat="server" TextMode="MultiLine" Rows="3" Width="100%"></asp:TextBox>
            </div>
        </ItemTemplate>
    </asp:Repeater>

分数段
最低要求正确答案：
点值


组指令










此问题组的评论（如果未评分，则需要）

这是什么意思：“用户编写问题，并将生成的问题保存到数据库。”？当您只知道uer想要一个列表框时，您将如何填充像ListBox这样的控件？我想您将看到两个不同的UI来构建。第一个是创建一个UI，允许您创建和管理问题和可能的答案。第二个问题是如何获取存储的数据并呈现一个表单供用户交互以回答问题。

static class ControlFactory {
  public static Control Create(string type) {
    if ("TextBox".Equals(type))
      return new TextBox();

    if ("RadioButton".Equals(type)) 
      return new RadioButtonList();
  }
}

    <asp:Repeater ID="Repeater1" runat="server">
        <ItemTemplate>
            <div class="questiongroup">
                <asp:HiddenField runat="server" ID="lblQuestionGroupId" Value='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "QuestionGroupId").ToString()) %>'>
                </asp:HiddenField>
                <asp:HiddenField runat="server" ID="hfSortOrder" Value='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "SortOrder").ToString()) %>'>
                </asp:HiddenField>
                <asp:HiddenField runat="server" ID="hdnPointsAwarded" Value='0'></asp:HiddenField>
                <br />
                <h3><asp:Label runat="server" ID="txtQuestionGroupName" MaxLength="50" Columns="50" Text='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "QuestionGroupName").ToString()) %>'></asp:Label>
                </h3>
                Score Section
                <asp:CheckBox runat="server" ID="chkIsScoreSection" Enabled="false" TabIndex="-1"
                    Checked='<%# Convert.ToBoolean(DataBinder.Eval(Container.DataItem, "IsScoreSection")) %>' />
                Minimum required correct answers:
                <asp:Label runat="server" ID="lblMinimumForScore" MaxLength="3" Columns="3" Text='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "CommentsRequiredMinimumYesAnswers").ToString()) %>'></asp:Label>
                  Point Value <asp:Label ID="lblPossiblePoints" runat="server" Text='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "PossiblePoints").ToString()) %>' />
                          <br />
                Group Instructions
                <br />
                <asp:Label runat="server" ID="lblGroupInstructions" TextMode="MultiLine" Columns="50" Rows="3"
                    Text='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "GroupInstructions").ToString()) %>'></asp:Label>
                <br />
                <div class='questionseditor'>
                </div>
                <br />
                <div class="questionsdiv">
                    <asp:Repeater ID="childRepeater" runat="server" DataSource='<%# ((DataRowView)Container.DataItem).Row.GetChildRows("Relation2") %>'>
                        <ItemTemplate>
                        <div class="question">
                            <asp:HiddenField ID="hdnQuestionType" runat="server" Value='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) %>' />
                            <asp:HiddenField ID="hdnQuestionId" runat="server" Value='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionId\"]").ToString()) %>' />
                            <asp:HiddenField ID="hfQuestionSortOrder" runat="server" Value='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"SortOrder\"]").ToString()) %>' />
                            <asp:RequiredFieldValidator SetFocusOnError="True" ID="YesNoForScoreRequiredFieldValidator" runat="server"
                                ControlToValidate="lstYesNoForScore" Display="Dynamic" ErrorMessage="Required<br />"
                                Enabled='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "1" %>'></asp:RequiredFieldValidator>
                            <asp:RequiredFieldValidator SetFocusOnError="True" ID="MemoRequiredFieldValidator" runat="server" ControlToValidate="txtMemoAnswer"
                                Display="Dynamic" ErrorMessage="Required<br />" 
                                Enabled='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "2" %>'></asp:RequiredFieldValidator>
                            <asp:RequiredFieldValidator SetFocusOnError="True" ID="NumericAnswerRequiredFieldValidator" runat="server"
                                ControlToValidate="txtNumericAnswer" Display="Dynamic" ErrorMessage="Required<br />"
                                Enabled='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "3" %>'></asp:RequiredFieldValidator>
                            <asp:RegularExpressionValidator SetFocusOnError="True" Display="Dynamic" runat="server" ID="NumericTextRegexValidator"
                                ValidationExpression="^\d*[0-9](|.\d*[0-9]|,\d*[0-9])?$" Enabled='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "3" %>'
                                ErrorMessage="*Invalid<br />" ControlToValidate="txtNumericAnswer"></asp:RegularExpressionValidator>
                            <asp:RequiredFieldValidator SetFocusOnError="True" ID="RequiredFieldValidator1" runat="server" ControlToValidate="lstYesNoNonScored"
                                Display="Dynamic" ErrorMessage="Required<br />" Enabled='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "5" %>'></asp:RequiredFieldValidator>
                            <asp:Label ID="lblQuestionText" runat="Server" Text='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionText\"]").ToString()) %>'></asp:Label><br />
                            <asp:RadioButtonList runat="server" ID="lstYesNoForScore" RepeatDirection="Horizontal"
                                Visible='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "1" %>'>
                                <asp:ListItem Text="Yes" Value="1"></asp:ListItem>
                                <asp:ListItem Text="No *" Value="0"></asp:ListItem>
                            </asp:RadioButtonList>
                            <asp:TextBox ID="txtMemoAnswer" runat="server" Visible='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "2" %>'
                                TextMode="MultiLine" Rows="3" Width="100%"></asp:TextBox>
                            <asp:TextBox ID="txtNumericAnswer" runat="server" Visible='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "3" %>'
                                cols="5"></asp:TextBox>
                            <uc1:MultipleChoiceControl ID="MultipleChoiceControl1" runat="server" Visible='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "4" %>'
                                QuestionId='<%# Convert.ToInt32(DataBinder.Eval(Container.DataItem, "[\"QuestionId\"]")) %>' />
                            <asp:RadioButtonList runat="server" ID="lstYesNoNonScored" RepeatDirection="Horizontal"
                                Visible='<%#  Microsoft.Security.Application.AntiXss.GetSafeHtmlFragment(  DataBinder.Eval(Container.DataItem, "[\"QuestionTypeId\"]").ToString()) == "5" %>'>
                                <asp:ListItem Text="Yes" Value="1"></asp:ListItem>
                                <asp:ListItem Text="No" Value="0"></asp:ListItem>
                            </asp:RadioButtonList>
                            <br />
                            </div>
                        </ItemTemplate>
                    </asp:Repeater>
                </div>
                Comments for this Question Group (Required if score not awarded)
                <asp:TextBox ID="txtGroupComments" runat="server" TextMode="MultiLine" Rows="3" Width="100%"></asp:TextBox>
            </div>
        </ItemTemplate>
    </asp:Repeater>