我在网页中有多个下拉列表,如果用户选择一个名为“禁用所有”的复选框,则希望禁用所有下拉列表。到目前为止,我已经编写了以下代码,但它没有起作用。请问有什么建议吗?
foreach (Control c in this.Page.Controls)
{
if (c is DropDownList)
((DropDownList)(c)).Enabled = false;
}
我在网页中有多个下拉列表,如果用户选择一个名为“禁用所有”的复选框,则希望禁用所有下拉列表。到目前为止,我已经编写了以下代码,但它没有起作用。请问有什么建议吗?
foreach (Control c in this.Page.Controls)
{
if (c is DropDownList)
((DropDownList)(c)).Enabled = false;
}
protected void DisableControls(Control parent, bool State) {
foreach(Control c in parent.Controls) {
if (c is DropDownList) {
((DropDownList)(c)).Enabled = State;
}
DisableControls(c, State);
}
}
那么就这样调用它:
protected void Event_Name(...) {
DisableControls(Page,false); // use whatever top-most control has all the dropdowns or just the page control
} // divs, tables etc. can be called through adding runat="server" property
我知道这是一个旧帖子,但这就是我刚刚解决这个问题的方法。根据标题“如何禁用ASP.NET页面中的所有控件?”,我使用了反射来实现这一点;它将适用于所有具有Enabled属性的控件类型。只需调用DisableControls并传入父控件(即Form)。
C#:
private void DisableControls(System.Web.UI.Control control)
{
foreach (System.Web.UI.Control c in control.Controls)
{
// Get the Enabled property by reflection.
Type type = c.GetType();
PropertyInfo prop = type.GetProperty("Enabled");
// Set it to False to disable the control.
if (prop != null)
{
prop.SetValue(c, false, null);
}
// Recurse into child controls.
if (c.Controls.Count > 0)
{
this.DisableControls(c);
}
}
}
VB:
Private Sub DisableControls(control As System.Web.UI.Control)
For Each c As System.Web.UI.Control In control.Controls
' Get the Enabled property by reflection.
Dim type As Type = c.GetType
Dim prop As PropertyInfo = type.GetProperty("Enabled")
' Set it to False to disable the control.
If Not prop Is Nothing Then
prop.SetValue(c, False, Nothing)
End If
' Recurse into child controls.
If c.Controls.Count > 0 Then
Me.DisableControls(c)
End If
Next
End Sub
如果您要禁用多个控件,最好将它们全部放在一个面板中,然后只需启用/禁用该面板即可。
在页面上需要禁用的区域周围放置面板:
< asp:Panel ID="pnlPage" runat="server" >
...
< /asp:Panel >
在Page_Load中:
If Not Me.Page.IsPostBack Then
Me.pnlPage.Enabled = False
End If
...或者C#等效语言。 :o)
protected void Page_Load(object sender, EventArgs e)
{
DisableChilds(this.Page);
}
private void DisableChilds(Control ctrl)
{
foreach (Control c in ctrl.Controls)
{
DisableChilds(c);
if (c is DropDownList)
{
((DropDownList)(c)).Enabled = false;
}
}
}
我曾经使用ASP.Net和HTML控件,我的写法如下:
public void DisableForm(ControlCollection ctrls)
{
foreach (Control ctrl in ctrls)
{
if (ctrl is TextBox)
((TextBox)ctrl).Enabled = false;
if (ctrl is Button)
((Button)ctrl).Enabled = false;
else if (ctrl is DropDownList)
((DropDownList)ctrl).Enabled = false;
else if (ctrl is CheckBox)
((CheckBox)ctrl).Enabled = false;
else if (ctrl is RadioButton)
((RadioButton)ctrl).Enabled = false;
else if (ctrl is HtmlInputButton)
((HtmlInputButton)ctrl).Disabled = true;
else if (ctrl is HtmlInputText)
((HtmlInputText)ctrl).Disabled = true;
else if (ctrl is HtmlSelect)
((HtmlSelect)ctrl).Disabled = true;
else if (ctrl is HtmlInputCheckBox)
((HtmlInputCheckBox)ctrl).Disabled = true;
else if (ctrl is HtmlInputRadioButton)
((HtmlInputRadioButton)ctrl).Disabled = true;
DisableForm(ctrl.Controls);
}
}
DisableForm(Page.Controls);
private void ControlStateSwitch(bool state)
{
foreach (var x in from Control c in Page.Controls from Control x in c.Controls select x)
if (ctrl is ASPxTextBox)
((ASPxTextBox)x).Enabled = status;
else if (x is ASPxDateEdit)
((ASPxDateEdit)x).Enabled = status;
}
我使用linq方法。在使用devExpress时,您必须包含DevExpress.Web.ASPxEditors库。
For Each c As Control In parentControl.Controls
If TypeOf (c) Is CheckBox Then
CType(c, CheckBox).Enabled = enable
ElseIf TypeOf (c) Is RadioButtonList Then
CType(c, RadioButtonList).Enabled = enable
End If
SetControls(c)
Next
End Sub
<body>
<form id="form1" runat="server">
...
</form>
</body>
代码后台:
protected void Page_Load(object sender, EventArgs e)
{
form1.Disabled = true;
}
当然,这也会禁用您的复选框,因此您将无法单击复选框以重新启用控件。