Question

我使用以下方法递归地在asp.net页面上查找控件：

    /// <summary>
    /// Searches recursively for a server control with the specified id parameter.
    /// </summary>
    /// <param name="start">The start.</param>
    /// <param name="id">The id.</param>
    /// <returns>A <see cref="Control"/></returns>
    public static Control FindControl(Control start, string id)
    {

        Control foundControl;
        if (start == null)
            return null;

        foundControl = start.FindControl(id);
        if (foundControl != null)
            return foundControl;

        foreach (Control c in start.Controls)
        {
            foundControl = FindControl(c, id);
            if (foundControl != null)
                return foundControl;
        }

        return null;
    }

我遇到了问题，因为它返回了错误的控件。我将问题跟踪到标准FindControl方法，并通过检查返回的控件的ID确实与请求的ID匹配来修复它：

    foundControl = start.FindControl(id);
        if (foundControl != null && foundControl.ID == id)
            return foundControl;

我的问题是为什么start.FindControl（id）会返回一个与所请求的id不匹配的控件？

Answer 1

我用

static class ControlExtension
    {
        public static IEnumerable<Control> GetAllControls(this Control parent)
        {
            foreach (Control control in parent.Controls)
            {
                yield return control;
                foreach (Control descendant in control.GetAllControls())
                {
                    yield return descendant;
                }
            }
        }
    }

并致电

var foundControl =  Page.GetAllControls().Where(c => c.ID = id);

编辑：

也许不是叫它开始搜索

 foundControl = start.FindControl(id);

你应该从

开始

foundControl = FindControl(start, id);

FindControl在我的递归方法中得到错误的控件

1 个答案: