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cypress/docs/source/api/commands/invoke.md
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2017-05-23 17:17:27 -04:00

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---
title: invoke
comments: true
description: ''
---
`cy.invoke` invokes functions on the current subject.
If you want to call a regular property that is not a function on the current subject, use [`cy.its`](https://on.cypress.io/api/its).
| | |
|--- | --- |
| **Returns** | the return value of the invoked property |
| **Timeout** | `cy.invoke` cannot timeout unless you've added assertions. The assertions will retry for the duration of [`defaultCommandTimeout`](https://on.cypress.io/guides/configuration#timeouts) |
# [cy.invoke( *functionName* )](#function-usage)
Invokes the function with the specified name
# [cy.invoke( *functionName*, **arguments* )](#function-with-arguments-usage)
Invokes the function with the specified name and forwards any additional arguments to the function call. There are no limits to the number of arguments.
# Function Usage
## Assert on a function after invoke
```javascript
var fn = function(){
return 'bar'
}
cy.wrap({foo: fn}).invoke('foo').should('eq', 'bar') // true
```
{% note info Using cy.invoke('text') %}
[Check out our example recipe where we use cy.invoke('text') to test against HTML content](https://github.com/cypress-io/cypress-example-recipes/blob/master/cypress/integration/bootstrapping_app_test_data_spec.js)
{% endnote %}
## Properties that are functions are invoked
```javascript
// force a hidden div to be 'display: block'
// so we can interact with its children elements
cy
.get('div.container').should('be.hidden') // true
.invoke('show') // call the jquery method 'show' on the 'div.container'
.should('be.visible') // true
.find('input').type('Cypress is great')
```
{% note info Using cy.invoke('show') and cy.invoke('trigger') %}
[Check out our example recipe where we use cy.invoke('show') and cy.invoke('trigger') to click an element that is only visible on hover](https://github.com/cypress-io/cypress-example-recipes/blob/master/cypress/integration/hover_hidden_elements.js)
{% endnote %}
## Useful for 3rd party plugins
```javascript
// as a slightly verbose approach
cy.get('input').invoke('getKendoDropDownList').then(function(dropDownList){
// the return of $input.getKendoDropDownList() has now become the new subject
// whatever the select method returns becomes the next subject after this
return dropDownList.select('apples')
})
```
## We can rewrite the previous example in a more terse way and add an assertion.
```javascript
cy
.get('input')
.invoke('getKendoDropDownList')
.invoke('select', 'apples')
.its('val').should('match', /apples/)
```
# Function with Arguments Usage
## Send specific arguments to the function
```javascript
var fn = function(a, b, c){
return a + b + c
}
cy
.wrap({sum: fn})
.invoke('sum', 2, 4, 6)
.should('be.gt', 10) // true
.and('be.lt', 20) // true
```
{% note info Using cy.invoke('removeAttr', 'target') %}
[Check out our example recipe where we use cy.invoke('removeAttr', 'target') to test clicking on a link without opening in a new tab](https://github.com/cypress-io/cypress-example-recipes/blob/master/cypress/integration/tab_handling_anchor_links_spec.js)
{% endnote %}
## Arguments are automatically forwarded to the function
```javascript
cy
.get('img').invoke('attr', 'src')
.should('include', 'myLogo')
```
# See also
- [its](https://on.cypress.io/api/its)
- [wrap](https://on.cypress.io/api/wrap)
- [then](https://on.cypress.io/api/then)
- [stub](https://on.cypress.io/api/stub)
- [spy](https://on.cypress.io/api/spy)