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RadSearchBox has an "EnableAutoComplete" property that controls the AutoComplete feature.

When AutoComplete is disabled the control resembles a simple textbox. It can still have a collection of image buttons. The Default Search button can also be visible. Pressing enter while typing in the control or clicking on the default search button will trigger the control’s default event, containing the value from the input field.

searchbox autocomplete false

When AutoComplete is enabled the control will filter an underlying database based on the text typed in the input and display the results in a dropdown, positioned under the SearchBox. In order for this to work the control must be bound to a datasource, ODataDataSource, WebService. It’s important to note that the results shown in the dropdown will not be instances of a public "Item" class. They will be directly rendered on the client with a property containing the dataItem attached to the rendered containing element. This dataItem will contain the additional values of the fields defined in the DataKeyNames Collection.

When AutoComplete is enabled the following properties can be used:

  • MinFilterLength - determines the minimum number of characters that should be typed in the searchbox input before the dropdown with autocomplete suggestions is shown. It's default value is 1 and in this case the drop-down will be shown immediately after the first character is typed.

  • MaxResultCount - sets the maximum number of results that will appear in the dropdown. Its default value is "-1", meaning that all the results found will be displayed in the dropdown. When this value is set, a "Show all results" button appears at the bottom of the dropdown Clicking this button will load all corresponding results.

searchbox show all results

When a WebService binding scenario is implemented and you need to use the "Show All Results" button and manage its visibility, the following requirements needs to be met:

  • MaxResultCount should be set to a desirable value. Use the get_maxResultCount() client-side method to pass its value to the web service

  • A custom calculation in the WebService needs to be implemented, so you could check if the "Show All Results" button needs to be visible. For example, if the entries count returned from the data source match the MaxResultCount value - the "Show All "Results" should not be visible. In this case you could toggle its Visible state by simply setting EndOfItems property of the SearchBoxData object in the following manner:

SearchBoxData data = new SearchBoxData();
data.EndOfItems = true;

Dim data As New SearchBoxData()
data.EndOfItems = True

In cases when MaxResultCount property is used in RadSearchBox and the DataSourceSelect event is handled manually in order for Show All Results button to appear correctly, we recommend that the amount of items that will be selected should be at least with one item greater than MaxResultCount .

The control can also have a Client or Server ItemTemplate, as well as a DropDown Header or Footer Template.

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