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C# Interactive in Visual Studio

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C# Interactive in Visual Studio

C# Interactive is an interesting REPL editor you can use in Visual Studio. Read on to learn how to set it up and use it for your project.

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In this article, we will learn how to use C# Interactive in Visual Studio. The C# Interactive window has been a part of Visual Studio since the Visual Studio 2015 update 1 release. In this article, I am using Visual Studio 2017 for demonstration purposes. C# Interactive is a REPL Editor, i.e. Read-Evaluate-Print-Loop with an advanced editor. With the C# Interactive window, we can test our code snippet without compiling or running the complete code.

Let's Begin:

Open C# Interactive window in Visual Studio. We can open C# Interactive window in multiple ways:

  • From Menu Bar: Go to View Menu then move the cursor to Other Windows and then click on C# Interactive.

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  • From context box: Right click on the .cs file and then click on Execute in Interactive (shortcut is Ctrl+E, Ctrl+E).

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  • From Visual Studio command prompt: Open Visual Studio Developer command prompt.

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Then type csi and press enter. C# Interactive mode will be available in the command prompt.

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The C# Interactive window has 4 options in the window that is as below:

  1. Reset: Reset will reset all the DLLs, methods, etc., loaded in the C# Interactive window.

  2. Clear: Clear will clear the screen of the C# Interactive Window.

  3. History Previous: For checking the previous step/command executed in the C# Interactive Window.

  4. History Next: For checking the next step/command executed in the C# Interactive Window.

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Execute Code in C# Interactive Window

We can execute C# code in the interactive window easily. In the below example, I have declared a string variable and displayed the output in the C# Interactive Window. C# Interactive window supports C# 6 and C# 7 as well.

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Intelligence feature is also available in the Interactive window, which makes it easy to use.

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We can execute any code block in the Interactive Window. For this, we have to just select the method which we want to test/access in the C# Interactive Window. Check the below example, I have created a Calculator class which has an Add, Subtract, Multiply, and Divide method.

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Now select the method or function you want to test in the C# Interactive window and right-click and select Execute in Interactive.

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Test the method by passing the parameter value in the method.

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We can also load the DLL in REPL with the help of the #r command, followed by the path of the DLL to load in the C# Interactive Window.

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C# Interactive Window also supports error handling in both compile time as well as runtime. Check the below screenshot:

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Hope this will help you. Thanks!

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web dev ,visual studio ,c# ,tutorial ,repl

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