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

By Tan Lee Published on Mar 01, 2025 84

If you attempt to use a LINQ extension method like Select() to transform elements of a list but haven't included using System.Linq;, you may encounter a compiler error such as:

How to Read XML element attributes with XElement in LINQ

By Tan Lee Published on Mar 01, 2025 94

XML elements can contain attributes, which are key-value pairs. To read these attributes, you can use XElement to parse the XML string (from the LINQ-to-XML API).

How to Use XmlSerializer to serialize in C#

By Tan Lee Published on Mar 01, 2025 126

To use XmlSerializer to serialize objects in C#, you need to follow these steps:

How to Handle a Request with application/json Content in ASP.NET Core

By Tan Lee Published on Mar 01, 2025 230

When a request comes into your action method, the ASP.NET Core framework attempts to find the correct InputFormatter to deserialize the incoming data.

How to receive a request with text/plain content in ASP.NET Core

By Tan Lee Published on Mar 01, 2025 268

When a request is received by your ASP.NET Core application and the action method has parameters, the framework tries to find an appropriate InputFormatter to deserialize the request body.

How to receive a file in a web API request in ASP.NET Core

By Tan Lee Published on Mar 01, 2025 260

When a client uploads a file in a multipart/form-data request, it is captured in an IFormFile object. This object contains metadata about the file, such as the file's name, and exposes the file's content as a stream, enabling you to either save or process the file as needed.

How to receive requests with XML content in ASP.NET Core

By Tan Lee Published on Mar 01, 2025 87

Receiving requests with XML content in ASP.NET Core is quite simple. You only need to register the built-in XML InputFormatter to handle XML content, otherwise, you'll encounter 415 – Unsupported Media Type errors.

How to parse XML with XElement in LINQ

By Tan Lee Published on Mar 01, 2025 86

The XElement class (from the LINQ-to-XML API) is a powerful tool for parsing and manipulating XML in memory. It allows you to search for XML elements, retrieve attributes, and modify values.

Attribute constructor has an invalid parameter type

By Tan Lee Published on Mar 01, 2025 131

To fix the "Attribute constructor has an invalid parameter type" error, you need to ensure that the constructor of your custom attribute is using a valid parameter type.

How to Download Crystal Reports for Visual Studio 2019

By Tan Lee Published on May 31, 2024 2.37K

To download and install Crystal Reports for Visual Studio 2019, follow these steps.

How to sign code with a certificate

By Tan Lee Published on Feb 28, 2025 152

Signing code with a certificate ensures the authenticity and integrity of your software. It involves applying a digital signature to your executable files or scripts using a code signing certificate.

Sequence contains no elements

By Tan Lee Published on Feb 28, 2025 189

When you call .Single() on an IEnumerable that is empty or contains more than one element, you encounter the following exception:

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