将 asp:textbox 可见属性更改为 true 的 Javascript
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Javascript to change asp:textbox visible property to true
提问by user2484849
I am trying to create an form in which a textbox should be shown or hidden based on the dropdown & also validate the textbox if it is shown only.
我正在尝试创建一个表单，其中应根据下拉列表显示或隐藏文本框，并且如果仅显示文本框，则还验证该文本框。
Can anyone help me in this?
任何人都可以帮助我吗？
<asp:DropDownList
ID="txt_days"
CssClass="txt_drpbx"
runat="server"
siz="10"
>
<asp:ListItem Text="Select" Value="0"></asp:ListItem>
<asp:ListItem Text="1" Value="1"></asp:ListItem>
<asp:ListItem Text="2" Value="2"></asp:ListItem>
</asp:DropDownList>
<asp:RequiredFieldValidator
ID="RequiredFieldValidator6"
runat="server"
ControlToValidate="txt_days"
ForeColor="Red"
ErrorMessage="Please Select No of days on leave"
InitialValue="0"
ValidationGroup="fdbk_chk"
>*</asp:RequiredFieldValidator>
<asp:TextBox
ID="txt_todate"
runat="server"
ReadOnly="true"
Visible="false"
CssClass="txt_bx"
></asp:TextBox>
<asp:RequiredFieldValidator
ID="RequiredFieldValidator1"
runat="server"
ControlToValidate="txt_todate"
ForeColor="Red"
ErrorMessage="Please Select Feedback Given For"
ValidationGroup="fdbk_chk"
>*</asp:RequiredFieldValidator>
<asp:Button
ID="btn_submit"
Text="Submit"
CssClass="btn_button"
runat="server"
onclick="btn_submit_Click"
ValidationGroup="fdbk_chk"
/>
<asp:ValidationSummary
ID="ValidationSummary1"
runat="server"
HeaderText="Some fields are missing"
ShowMessageBox="True"
ShowSummary="False"
ValidationGroup="fdbk_chk"
/>
回答by Altaf Sami
Try this:
试试这个：
<script>
function ShowHideTextBox(ddlId)
{
var ddl = document.getElementById(ddlId.id);
if(ddl.value == 1) //your condition
{
document.getElementById('txt_todate').style.display = 'none';
}
else
{
document.getElementById('txt_todate').style.display = '';
}
}
<asp:DropDownList ID="txt_days" CssClass="txt_drpbx" runat="server" siz="10" onchange="ShowHideTextBox(this);"
<asp:TextBox ID="txt_todate" runat="server" ReadOnly="true" Visible="false" CssClass="txt_bx"></asp:TextBox>
回答by CocLn
Instead of using visible, set its css to display:none
而不是使用可见，将其 css 设置为 display:none
<asp:TextBox ID="txt_todate" runat="server" style="display:none;" CssClass="txt_bx">
</asp:TextBox>
and add your dropdownlist onchange
并添加您的下拉列表 onchange
<asp:DropDownList ID="ddlDays" CssClass="txt_drpbx" runat="server" onchange="ShowHide();">
<asp:ListItem Text="Select" Value="0"></asp:ListItem>
<asp:ListItem Text="Show" Value="1"></asp:ListItem>
<asp:ListItem Text="Hide" Value="2"></asp:ListItem>
</asp:DropDownList>
in script;
在脚本中；
<script type="text/javascript">
function ShowHide(){
var value = document.getElementById('ddlDays').value;
var theControl = document.getElementById("txt_todate");
if(value != 1){ // only when value is 1 it must show
theControl.style.display = "none";
}
else{
theControl.style.display = "block";
}
}
</script>
回答by JulyOrdinary
I tried display none at my end it was not working, but I was successful with visibility property. So, try this:
我尝试在最后显示 none 它不起作用，但我成功地使用了可见性属性。所以，试试这个：
function Validate()
{
var dropdown = document.getElementById('ID of the dropdown');
if(Condition which you want)
{
document.getElementById('txt_todate').style.visibility= true;
}
else
{
document.getElementById('txt_todate').style.visibility= false;
}
}
回答by Fran Cerezo
Control id on server side is not the same in client side. To be the same and to can use ID with javascript you must add to your server controls ClientIDMode="Static"
服务器端的控件 ID 与客户端的不同。为了相同并且可以将 ID 与 javascript 一起使用，您必须添加到您的服务器控件 ClientIDMode="Static"
As example:
例如：
<asp:DropDownList ID="ddlDays" ClientIDMode="Static" CssClass="txt_drpbx" runat="server" onchange="ShowHide();">
