ASP.NET向导控件和视图状态

Question

我有一个包含3个向导步骤的表单，当我点击按钮动态添加文本框时，效果很好，但当我进入下一步并点击添加以添加更多文本框，它会自动添加前一步中的所有文本框，然后如果我一直点击它，它会继续添加。

我该如何防止这种情况发生。

私有列表控件列表{收到{if（ViewState["controls"]==null）{ViewState["controls"]=new List（）；}return（List）ViewState["controls"]；}}

private int NextID
{
    get
    {
        return ControlsList.Count + 1;
    }
}

protected override void LoadViewState(object savedState)
{
    string section = Wizard1.ActiveStep.ID;
    int sectionNum = Wizard1.ActiveStepIndex;
    var control = Wizard1.ActiveStep.FindControl("Place" + sectionNum) as PlaceHolder;
    base.LoadViewState(savedState);
    int count = 0;
    foreach (string txtID in ControlsList)
    {
        if (count == 0)
        {
            control.Controls.Add(new LiteralControl("<tr>"));
        }
        TextBox txt = new TextBox();
        control.Controls.Add(new LiteralControl("<td>"));
        txt.ID = txtID;
        control.Controls.Add(txt);
        control.Controls.Add(new LiteralControl("</td>"));
        count = count + 1;
        if (count == 3)
        {
            control.Controls.Add(new LiteralControl("</tr>"));
            count = 0;
        }
    }
}

protected void AddControlButton_Click(object sender, EventArgs e)
{

    string section = Wizard1.ActiveStep.ID;
    int sectionNum = Wizard1.ActiveStepIndex;
    var control = Wizard1.ActiveStep.FindControl("Place" + sectionNum) as PlaceHolder;
    TextBox txt1 = new TextBox();
    TextBox txt2 = new TextBox();
    TextBox txt3 = new TextBox();

    txt1.ID = section.ToString() + "Size" + NextID.ToString();
    control.Controls.Add(new LiteralControl("<td>"));
    control.Controls.Add(txt1);
    control.Controls.Add(new LiteralControl("</td>"));
    ControlsList.Add(txt1.ID);
    txt2.ID = section.ToString() + "Description" + NextID.ToString();
    control.Controls.Add(new LiteralControl("<td>"));
    control.Controls.Add(txt2);
    control.Controls.Add(new LiteralControl("</td>"));
    ControlsList.Add(txt2.ID);
    txt3.ID = section.ToString() + "Quantity" + NextID.ToString();
    control.Controls.Add(new LiteralControl("<td>"));
    control.Controls.Add(txt3);
    control.Controls.Add(new LiteralControl("</td></tr>"));
    ControlsList.Add(txt3.ID);

}

Answer 1

您将所有动态文本框存储在ViewState中，然后ControlsList属性getter在构建文本框时返回整个列表。

我的建议是使用Session缓存，而不是ViewState，因为这将允许您区分文本框控件与每个向导步骤，如下所示：

Session["WizardStep1"] = listOfTextBoxesFromStep1;
Session["WizardStep2"] = listOfTextBoxesFromStep2;
Session["WizardStep3"] = listOfTextBoxesFromStep3;