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Query1 :” When using "CascadeTo", the "cascade" dropdownlist is not filtered”.
Based on your shared details we are unable to reproduce the issue when using the code from our online demo. We suspect that the issue may be caused because of the ID set in the CascadeTo property, you have to give the corresponding DropDownList’s ClientID to the CascaseTo property. Please ensure the ID given in your sample.
We have prepared cascading DropDownList sample and it is available below link:
Query 2: “When using "OnValueSelect" i receive and error "Sys.WebForms.PageRequestManager is undefined ".
We are unable to reproduce this error, so kindly share us the screenshots of the corresponding error and also provide the code snippets on how you have defined OnValueSelect event in your end and where do you use Sys.WebForms.PageRequestManager in your application? Provide us the details requested so that we can provide you an appropriate solution.
Please let me know if you have any questions.
You can also set “ ClientIDMode="Static" ” in the second dropdown and use the id as specified the below code,
<div class="control" style="float: left;">
<span class="txt">Select Group</span>
<ej:DropDownList ID="groupsList" runat="server" DataTextField="text" DataValueField="parentId" CascadeTo="countryList"
<div class="control" style="float: right;">
<span class="txt">Select Country</span>
<ej:Tab ID="UserTabs" runat="server">
<ej:TabItem ID="item1" runat="server">
<ej:DropDownList ID="countryList" runat="server" Enabled="false" ClientIDMode="Static">