Excel add-in and custom functions

As technology continues to evolve, the tools and platforms that developers use to create applications are also evolving. In this blog, we will explore how to create an Office Add-in with Excel custom functions using the Angular framework and the Yeoman generator.

The first step is to install the Yeoman generator for Office Add-ins using the following command:
npm install -g yo generator-office

Once the generator is installed, we can create a new Office Add-in project using the following command:
yo office

This command will prompt you to select the type of Office Add-in you want to create. In this case, we will select the Excel Add-in.
Next, we need to choose the framework we want to use to create our add-in. We will select Angular, We could also select React or HTML,CSS only if required based on requirements.

Once the project is generated, we can navigate to the project directory and run the following command to build and run the add-in:
npm start

This will build the add-in and start a local server where we can test our add-in in Excel.
The build files will be located in under dist folder in the root of the project.

Now that we have our add-in project set up, we can start creating our Excel custom functions.

Excel custom functions allow you to create your own functions that can be used in Excel formulas. To create a custom function, we need to open the Functions.ts file under Functions folder
Write the Function code:

export function double(input: number): number {
  return input * 2;
}

This function takes in a number and returns the number multiplied by 2.

Now we can use this function in Excel formulas like any other built-in function.
=double(A1)


This will take the value in cell A1, double it, and return the result.
In conclusion, creating an Office Add-in with Excel custom functions using the Angular framework and the Yeoman generator is a straightforward process. With just a few lines of code, we can create custom functions that can be used in Excel formulas, extending the functionality of Excel to fit our specific needs.