Derive Macro ag_grid_rs::ToJsValue

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#[derive(ToJsValue)]
{
    // Attributes available to this derive:
    #[js_value]
}

Expand description

Automatically derive the ToJsValue trait to enable the annotated type to be serialized to a wasm_bindgen::JsValue.

The macro can be applied either to structs with named fields, or fieldless enums.

Examples

Structs with named fields

The macro can be derived for any struct with named fields where all field types also implement ToJsValue. Most primitive types have a ToJsValue implemntation already. Given the following struct,

#[derive(ToJsValue)]
struct Data {
    first_value: String,
    second_value: bool
}

the following equivalent implementation would be generated:

impl ToJsValue for Data {
    fn to_js_value(&self) -> JsValue {
        let obj = js_sys::Object::new();
        // We actually use a custom implementation of Object which has a helper `set` method.
        obj.set("firstValue", self.first_value.to_js_value());
        obj.set("secondValue", self.second_value.to_js_value());
        obj.into()
    }
}

Note that the field names are converted to camelCase by default.

Supported attributes

At the the container-level:

#[js_value(skip_serializing_none)] - any top-level Option<T> which has a value of None will be omitted from the serialized object. When this flag is absent, i.e. by default, None values are serialized to JsValue::null().

At the field-level:

#[js_value(rename = "...")] - override the default camelCase name for the serialized field.

Fieldless enums

A fieldless enum, such as

derive(ToJsValue)
enum MoonPhase {
    New,
    FirstQuarter,
    ThirdQuarter,
    Full     
}

would produce an implementation equivalent to:

impl ToJsValue for MoonPhase {
    fn to_js_value(&self) -> JsValue{
        Self::New => JsValue::from_str("new"),
        Self::New => JsValue::from_str("firstQuarter"),
        Self::New => JsValue::from_str("ThirdQuarter"),
        Self::New => JsValue::from_str("full"),
    }
}

As with structs the default behaviour is to serialize the variant to camelCase.

Supported attributes

At the variant-level:

#[js_value(rename = "...")] - override the default camelCase name for the serialized variant.
#[js_value(serialize_as = "{placeholder}") - , where {placeholder} can be one of : null, undefined, true or false. Instead of the tagged variant being serialized to a string, it is instead serialized to one of the chosen literal JavaScript Values. It is useful if, for example, you have an enum with a Null variant and want it to be serialized to a a primitive null rather than the string "null".