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How to use String.Join() in C#

By Tan Lee Published on Mar 05, 2025 214

You can utilize String.Join() to convert a collection of items into a single string with a specified separator (like a comma).

Default access modifiers in C#

By Tan Lee Published on Mar 05, 2025 170

In C#, classes (and other types) have internal access by default, while class members (methods, properties, fields) are private by default.

internal vs protected in C#

By Tan Lee Published on Mar 05, 2025 147

The access modifiers public and private are straightforward: public means everything has access, while private restricts access solely to the class itself.

Synchronous operations are disallowed

By Tan Lee Published on Mar 04, 2025 218

When performing a synchronous I/O operation in ASP.NET Core (such as writing to a file), you may encounter the following exception:

How to convert hex string to byte array in C#

By Tan Lee Published on Mar 04, 2025 295

You can convert a hex string to a byte array in C# using a lookup table and bitwise operations for efficiency.

Enum flags allow you to store multiple values in a single enum variable or parameter. This is a great alternative to passing multiple boolean values. You set multiple values by using a bitwise OR operation.

How to call a static method using reflection in C#

By Tan Lee Published on Mar 04, 2025 321

To call a static method using reflection in C#, follow these steps:

InvalidArgument=Value of ‘0’ is not valid for ‘SelectedIndex’

By Tan Lee Published on Mar 04, 2025 165

You might encounter the following error when setting the SelectedIndex of a ComboBox:

How to Use string interpolation instead of string.Format in C#

By Tan Lee Published on Mar 04, 2025 203

Using string.Format() can lead to errors and runtime exceptions, making code harder to maintain. String interpolation provides a safer, more readable alternative.

How to Fill a Dropdown with Enum Values in C#

By Tan Lee Published on Mar 04, 2025 221

When you need to display enum values in a dropdown (ComboBox control with DropDownStyle=DropDown), it's best to populate the list dynamically instead of manually adding each value.

Cannot use a lambda expression as an argument to a dynamically dispatched operation

By Tan Lee Published on Mar 04, 2025 130

You may encounter the following compiler error when attempting to use a lambda expression on a dynamic object:

How to consume an SSE endpoint with HttpClient in C#

By Tan Lee Published on Mar 04, 2025 304

You can consume a Server-Sent Events (SSE) endpoint using HttpClient in C# by reading the event stream asynchronously.

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