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Expression

Expressions will often be used as simple placeholders to map data from the source entity. Most values in schemas and partial schemas can be expressed. An expression is identified by using curly brackets {}:

"headline": "{p.title}"

A value that support expression can have multiple expressions:

"headline": "{p.title}: {p.subTitle}"

In combination with regular text:

"headline": "Blog post: {p.title}"

Null check​

Trying to access properties of a none existing object will cause the view generation to fail. If that's not intended add a null check using ?.

In the following example headline will be set to the value of p.meta.description. If p.meta is null (or doesn't exist) headline.

"description": "{p.meta?.description}"

Null coalescing​

"headline": "{p.title ?? p.header}"

Combined with null check:

"headline": "{p.meta?.description ?? p.description}"

The expression can also be grouped using parentheses:

"x": "{(p.a ?? p.b) ?? p.c}"

Accessing properties​

Accessing properties can be done by typing p. followed by the name of the property.

Property with default type (string)
{
  "triggers": {
    "umbraco": ["frontPage"]
  },
  "route": {
    "url": "{url}"
  },
  "properties": {
    "headline": "{p.title}"
  }
}

The default type of a property is a string. If you need another property type, simply change your property to an object and use type and value.

Property with type number
{
  "triggers": {
    "umbraco": ["frontPage"]
  },
  "route": {
    "url": "{url}"
  },
  "properties": {
    "stock": {
      "type": "number",
      "value": "{p.inventoryQuantity}"
    }
  }
}