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When you want to convert a DateTime to a string, use ToString(). By default, this converts the DateTime to a string using the current culture’s date/time format (from the OS). In most cases, you’ll want to specify the format to use. You can do this by passing in a format string consisting of format specifier … Read more
Use DateTime.Now to get the current date/time, like this: This outputs the system’s current date/time: Note: By default, it uses the current culture’s date format (from the OS). This is showing the US date format – MM/dd/yyyy. DateTime.Now is the local date/time from the system where the code is executing. Keep that in mind if … Read more
When you need to let the user select a date and/or time of day, you can use the DateTimePicker control: You can set the control properties in the UI or programmatically: If you don’t set an initial value, it’ll default to DateTime.Now (at the time the code is executed). The value the user picked is … Read more
You can use JsonConverterAttribute (from System.Text.Json) to apply a specific JsonConverter to a property. Apply this attribute on a property and specify the JsonConverter type to use, like this: In this example, it’s applying ExpirationDateConverter (a custom JSON converter) to handle the ExpirationDate. For reference, here’s ExpirationDateConverter’s definition: Now serialize the object to JSON: Here’s … Read more
When you’re using Moq to set up a mocked method, you can use Callback() to capture the parameters passed into the mocked method: There are two main use cases for capturing parameters in a test: In this article, I’ll show examples of using Callback() in those two scenarios, and then I’ll explain some problems to … Read more
I was reading about logging in ASP.NET when I came across this statement about logging to the database: When logging to SQL Server, don’t do so directly. Instead, add log messages to an in-memory queue and have a background worker dequeue and insert data to SQL Server. Paraphrased from Microsoft – No asynchronous logger methods … Read more
When you need to insert multiple rows into the database, consider doing a Bulk Insert instead of inserting one row at a time. Bulk Insertions are up to 20x faster than executing SQL Insert repeatedly. The simplest way to do a SQL Bulk Insert is by using the built-in SqlBulkCopy (from System.Data.SqlClient) with a DataTable. … Read more
You can add default method implementations (and constants) to interfaces (in C# 7+), like this: Note: The Log() method is converting the DateTime to a string with a custom format and including it with the logging message. This outputs the following: Microsoft’s stated purpose for this feature is that it allows you add methods to … Read more
Interpolated strings have the following structure: {variable:format}. Typically you exclude the format, so they normally look like this: $”My name is {name}”. Here’s how to use format strings with an interpolated string: This outputs the following: This is the equivalent of using string.Format() like this: Read more about why you should use string interpolation instead … Read more
The Channel class (from System.Threading.Channels) is a non-blocking async queue. It implements the producer-consumer pattern, which has two parts: Compare this with using BlockingCollection, which is a blocking concurrent queue. In this article, I’ll show how to use a Channel. 1 – Create the Channel The first step is to create the Channel object. Here’s … Read more
I want to log method calls, including their parameter names and values, and what called the method. I want to minimize the amount of coding involved. For example: What options are available? In this article I’ll explain how to use the simple built-in approach. 1 – Create LogMethodCall() utility method The System.Diagnostics.StackFrame class gives us … Read more