Adding Logic

The Digia Dashboard allows you to enrich your app’s behavior by adding custom expressions and logic directly from the UI. This can be done in any field that supports dynamic values — simply click on the dynamic field icon [<>] and the Code Dialog will open.

Within this dialog, you can:

✅ Use built-in expression functions ✅ Nest expressions ✅ Combine expressions with your own JavaScript functions

Preview Value is used for the Design mode and has no impact on the actual expression.

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🧠 Built-In Functions

Digia provides many built-in functions out of the box. These are grouped into the following categories:

Category	Description
JSON	Work with JSON objects and extract values
Math	Perform numeric calculations
DateTime	Parse, convert, and format dates
String	Manipulate string values
Logical	Add comparisons and logical operations

These functions can be mixed and matched in expressions and can also be nested within each other.

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📌 Examples

Expression	Description
jsonGet(response.data, 'users[0].id')	Returns the id of the first user in the list
isNotEqual(2, 2)	Returns false because both arguments are equal
isoFormat('2024-06-03T23:42:36Z', 'Do MMMM')	Converts ISO string into a readable format (3rd June)

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🔁 Nested Expressions

Expressions can reference other expressions:

isNotEqual(
  jsonGet(response.data, 'users[0].id'),
  5
)

In this example, the platform first resolves jsonGet(...), and then evaluates the result against the number 5.

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🧩 Custom JavaScript Functions

If the built-in expression language isn’t enough, you can write your own JavaScript function and call it from the code dialog.

Example:

// Example in your functions
//Arguments are passed as an array
function calculateDiscount(args) {
  var price = args[0];
  return price * 0.8;
}

// Called in Digia expression
js.eval('calculateDiscount', product.price)

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✅ Summary

Feature	Available
Built-in expression functions	✅
Nested expressions	✅
Custom JavaScript invocation	✅
Combination of both	✅