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Custom Validation

The RadSpreadsheet control allows you to create your own custom Validation Dialog, where you can define the criteria and behavior for invalid data that suits best your scenario. You can achieve this, using the ValidationTemplate tag of the RadSpreadsheet control. The following steps will guide you trough the custom Data Validation dialog implementation:

  1. Create a WebUserControl, which will contain the layot and behavior of the custom Validation dialog. In the WebUserControl you can define preferable Criteria for data types and implement any further configuration for those types. Also, you can configure the behavior for handling the invalid data and Hint Message.

  2. Create JavaScript file that will be the actual connection to the Spreadsheet.ValidationView. In this javascript file, you will need to create the interface for the ValidationView object of the RadSpreadsheet and the markup of the newly created custom dialog. Manipulating the prototypes of the ValidationView you will have a full access and ability to implement or modify the behavior of the default controls in the view and apply your custom one.

  3. Create the RadSpreadsheet on your page, referencing the custom WebUserControl that contains the new Validation view (dialog) in the ValidationTemplate tag and provide a reference to the javascript file that serve as interface for ValidationView object of the RadSpreadsheet and the custom Validation dialog. At the end, the layout of the aspx page where the RadSpreadsheet is defined should look as simple as the below implementation:

<%@ Register Src="~/SpreadsheetValidation.ascx" TagPrefix="uc1" TagName="SpreadsheetValidation" %>
<form id="form1" runat="server">
    <telerik:RadScriptManager runat="server" />

    <script src="Scripts/ValidationView.js"></script>

    <telerik:RadSpreadsheet runat="server" ID="RadSpreadsheet1">
            <uc1:SpreadsheetValidation runat="server" ID="SpreadsheetValidation" />


You can investigate the entire setup and test the behavior of the RadSpreadsheet with Custom Validation dialog in this Code Library: Validation Template for RadSpreadsheet Code Library.

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