string-tolower

C# – How to update a file’s contents

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There are three ways to update a file’s content: Which option you pick depends on the file’s format and size. For example, if you’re writing to an existing CSV file, you’d append new lines to the end of the file. If you’re updating a JSON file, you’d read all the JSON content, make changes, then … Read more

CsvHelper – Header with name not found

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When your CSV header names don’t match your property names exactly, CsvHelper will throw an exception. For example, if your header name is “title” and your property name is “Title”, it’ll throw an exception like: HeaderValidationException: Header with name ‘Title'[0] was not found. If you don’t want to (or can’t) change the names to match, … Read more

Could not find an implementation of the query pattern for source type

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Problem Any time you try to use a Linq extension method (such as Select() to transform list elements) and you haven’t added ‘using System.Linq’, you’ll get a compiler error like this: Could not find an implementation of the query pattern for source type ‘Your Type’.  ‘Select’ not found. In newer versions, the error looks like … Read more