//// This code is part of Document Solutions for Word demos.// Copyright (c) MESCIUS inc. All rights reserved.//usingSystem;usingSystem.IO;usingSystem.Globalization;usingGrapeCity.Documents.Word; namespaceDsWordWeb.Demos{// This example shows how to deal with the 'data source with this name already exists' error.publicclassDataTplFixSpecifyDataSource {// Code demonstrating the problem:GcWordDocumentProblem() {usingvar oceans = File.OpenRead(Path.Combine("Resources", "data", "oceans.json"));usingvar oceans1 = File.OpenRead(Path.Combine("Resources", "data", "oceans.json"));var doc = newGcWordDocument(); doc.DataTemplate.DataSources.Add("ds", oceans); doc.DataTemplate.DataSources.Add("ds1", oceans1);// Incorrect: template tag is used without specifying the data source part.// It is allowed only if the template engine is able to resolve the tags.// But because in this case there are two data sources that both contain a field called 'name',// if causes an exception as the tag cannot be resolved: doc.Body.Paragraphs.Add("{{name}}"); doc.DataTemplate.Process(CultureInfo.GetCultureInfo("en-US"));return doc; } // Code demonstrating the fix:GcWordDocumentFix() {usingvar oceans = File.OpenRead(Path.Combine("Resources", "data", "oceans.json"));usingvar oceans1 = File.OpenRead(Path.Combine("Resources", "data", "oceans.json"));var doc = newGcWordDocument(); doc.DataTemplate.DataSources.Add("ds", oceans); doc.DataTemplate.DataSources.Add("ds1", oceans1);// Correct: use fully qualified data tags so there is no ambiguity: doc.Body.Paragraphs.Add("{{ds.name}}"); doc.DataTemplate.Process(CultureInfo.GetCultureInfo("en-US"));return doc; } publicGcWordDocumentCreateDocx() {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($"The error \"{ex.Message}\" occurred because the data template engine could not unambiguously resolve the data tag " +$"that was not fully qualified. " +$"The fix is to use fully qualified data tags.", doc.Styles[BuiltInStyleId.BlockText],InsertLocation.Start); }return doc; } }}