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Call Unity C# script functions from JavaScript

Call functions from your Unity project in your JavaScript plug-in or browser.
Read time 2 minutesLast updated 10 days ago
You might want to call some Unity code from your JavaScript plug-in or browser code. For example, you might want a JavaScript UI element that triggers a Unity behaviour and needs access to that method.
The recommended way to send data or notifications to the Unity C# script from the browser’s JavaScript is to use the 
SendMessage
function to call methods on GameObjects in your Unity project.

Use the SendMessage helper function

Use 
SendMessage
to call a Unity method of the Unity scripting API from JavaScript code.
There are some restrictions for what sort of methods you can pass. You can only call methods of a GameObject, not general C# methods attached to other objects. Also, only use 
SendMessage
to call a method if one of the following is true:
  • The method takes no parameters.
  • The method has one parameter and that parameter is a single string.
  • The method has one parameter and that parameter is a single number.
Methods with more than one parameter or with parameters of other types can't be called using 
SendMessage
.

Example SendMessage code

To make the call from a JavaScript plug-in embedded in your project, use the following code:
MyGameInstance.SendMessage(objectName, methodName, value);
  • objectName
    is the name of an object in your scene.
  • methodName
    is the name of a method in the script, currently attached to that object.
  • value
    can be a string, a number, or can be empty.
The following code is a further example that shows each of the types of methods that you can call with different parameters.
MyGameInstance.SendMessage('MyGameObject', 'MyFunction');MyGameInstance.SendMessage('MyGameObject', 'MyFunction', 5);MyGameInstance.SendMessage('MyGameObject', 'MyFunction', 'MyString');
To make a call from the global scope of the embedding page, refer to Call JavaScript functions from global scope.

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