//// This code is part of Document Solutions for Word demos.// Copyright (c) MESCIUS inc. All rights reserved.//using System;using System.IO;using GrapeCity.Documents.Word;
namespace DsWordWeb.Demos{    // This example shows how to deal with the 'item processed action is required' error.    public class DataTplFixBatchActionNeeded    {        // Code demonstrating the problem:        GcWordDocument Problem()        {            using var oceans = File.OpenRead(Path.Combine("Resources", "data", "oceans.json"));            var doc = new GcWordDocument();            doc.DataTemplate.DataSources.Add("ds", oceans);            doc.Body.Paragraphs.Add("{{ds.name}}");            // Incorrect: batch processing requires to specify an action that would be invoked            // after each root data item is processed. Such action could for example save the            // processed document instance containing the current record's data.            // Not specifying an action causes an exception:            doc.DataTemplate.BatchProcess(null);            return doc;        }
        // Code demonstrating the fix:        GcWordDocument Fix()        {            using var oceans = File.OpenRead(Path.Combine("Resources", "data", "oceans.json"));            var doc = new GcWordDocument();            doc.DataTemplate.DataSources.Add("ds", oceans);            doc.Body.Paragraphs.Add("{{ds.name}}");            // Correct: any (even empty) action except null is good enough for the BatchProcess call:            doc.DataTemplate.BatchProcess(() => { });            return doc;        }
        public GcWordDocument CreateDocx()        {            GcWordDocument doc;            try            {                // This fails:                doc = Problem();            }            catch (Exception ex)            {                // This works:                doc = Fix();                // Insert a brief explanation of the problem and the fix into the generated document:                doc.Body.Paragraphs.Insert(                    $"The error \"{ex.Message}\" occurred because the BatchProcess() method requires a non-null " +                    $"action to be specified that would be called as each root data item is processed. " +                    $"The fix is to specify an action (even an action that does nothing would do). " +                    $"Note that when the BatchProcess() method returns, the original template document " +                    $"with data tags rather than actual data is restored.",                    doc.Styles[BuiltInStyleId.BlockText],                    InsertLocation.Start);            }            return doc;        }    }}