I am not quite sure I understand the exact scenario, could you please elaborate on the subject? What exactly do you mean by "case where we are creating a new file"? You have implemented custom functionality to RadFileExplorer for creating new files?
You can get the value of the SearchPatterns in the page's from the RadFileExplorer's configuration using the corresponding property
 searchPatterns = RadFileExplorer1.Configuration.SearchPatterns;
Or, you can get the value of the explorer's search patterns inside the content provider using its SearchPatterns property.
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