# Javascript functions

The JS library exposes functions that you can use anywhere in your code. (just make sure the library is already loaded when calling one of these functions)

### Weglot.translate(payload, callback)

{% tabs %}
{% tab title="Parameters" %}

* payload(Object):
  * words(Array)
    * t(Integer): word type, see [word types reference](/api/reference.md#wordtype)
    * w(String): string to translate
  * languageTo(String): translation destination language code
* callback(Function)
  {% endtab %}

{% tab title="Response" %}
Promise containing translated strings
{% endtab %}

{% tab title="Example" %}

```javascript
Weglot.translate(
    {
    'words':[ { "t":1,"w": "Red" } ],
    'languageTo':'fr'
    } 
    , function(data) { console.log(data) }
);
```

{% endtab %}
{% endtabs %}

### Weglot.getCurrentLang(): String

{% tabs %}
{% tab title="Parameters" %}
None
{% endtab %}

{% tab title="Response" %}
String: the ISO 639-1 2-letter code of the current language on the page
{% endtab %}
{% endtabs %}

### Weglot.getLanguageName(code): String

{% tabs %}
{% tab title="Parameters" %}

* code(String): the ISO 639-1 2-letter code of [a language supported by Weglot](https://weglot.com/documentation/available-languages)
  {% endtab %}

{% tab title="Response" %}
String: the local name of the language, as defined by ISO 639-1

For example, calling `Weglot.getLanguageName("es")` returns `"Español"`
{% endtab %}
{% endtabs %}

### Weglot.getBestAvailableLanguage(): String <a href="#weglot-getlanguagename-code" id="weglot-getlanguagename-code"></a>

{% tabs %}
{% tab title="Parameters" %}
None
{% endtab %}

{% tab title="Response" %}

* code(String): the ISO 639-1 2-letter code of the best available language
  {% endtab %}
  {% endtabs %}

This function checks the visitors preferred languages, and finds the best match among the languages you support on Weglot. It's the function used internally when you use the `autoSwitch` function

### Weglot.search(term, callback): Boolean

{% tabs %}
{% tab title="Parameters" %}

* term(String): Any term written in the current language of the page.
* callback(Function): A function that will be called whenever the search term in the original language is available. Takes one String argument
  {% endtab %}

{% tab title="Response" %}
`true` if there is a search to be made (the current language of the page differs from the original language)

`false` if there is no search to be made. In this case the callback is called immediately with the original term
{% endtab %}
{% endtabs %}

### Weglot.switchTo(code): void

{% tabs %}
{% tab title="Parameters" %}

* code(String): the ISO 639-1 2-letter code of a language you're supporting on your website

  code is either **originalLanguage** or one of the **destinationLanguages**
  {% endtab %}

{% tab title="Response" %}
Nothing
{% endtab %}
{% endtabs %}

### Weglot.on(eventName, callback)

You can subscribe your own code to Weglot-specific events. When these events occur, the callback function you have defined will be called.

#### languageChanged (only JS integration)

This is called right after a language has changed on the page

```javascript
Weglot.on("languageChanged", callbackFunction)
```

The callback function will be called with two optional arguments:

1. newLanguage (String): the 2-letter code of the language the page changed to
2. previousLanguage (String): the 2-letter code of the previous language of the page

Example:

```javascript
Weglot.on("languageChanged", function(newLang, prevLang) {
    console.log("The language on the page just changed to (code): " + newLang)
    console.log("The full name of the language is: " + Weglot.getLanguageName(newLang))
})
```

{% hint style="warning" %}
This event is only available with our Javascript integration, not with subdomain or subdirectory integration.
{% endhint %}

#### initialized

This is called right after the call to **Weglot.initialize(options)** has been successful, but before the switchers are created and the page is translated

```javascript
Weglot.on("initialized", callbackFunction)
```

The callback function will be called with no argument.

{% hint style="info" %}
If you register your callback **after** Weglot has been initialized, this will have no effect.

To check whether Weglot is already initialized or not, you can read the boolean `Weglot.initialized`
{% endhint %}

#### switchersReady

This is called right after the switchers have been created.

```javascript
Weglot.on("switchersReady", callbackFunction)
```

The callback function will be called with one optional argument: `initialLanguage`

Example:

```javascript
Weglot.on("switchersReady", function(initialLanguage) {
  console.log("the switchers are ready, I can tweak them")
})
```

### Weglot.off(eventName, callback): Boolean

With `Weglot.off`, you can unsubscribe the events you subscribed to with `Weglot.on`

{% tabs %}
{% tab title="Parameters" %}
eventName(String): **mandatory field**, the name of the event you want to unsubscribe from

callbackFunction(Function): **optional field**, if you'd like to target a specific function
{% endtab %}

{% tab title="Response" %}
**true** if one or more events have been unregistered

**false** otherwise
{% endtab %}
{% endtabs %}

### Weglot.initialize(options): void

Called to initialize Weglot. See [Initialization code](/javascript/javascript.md#initialization-code)


---

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```
GET https://developers.weglot.com/javascript/javascript-functions.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

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