ReactJS: how to trigger form submit event from another event

Question

I've two react events:

1. Form submit event

   sendMessage: function(event){
       console.log(event);
       event.preventDefault();
   },
   

2. keyPress Event

   textareaKeypress: function(event){
       if (event.which == 13 && !event.shiftKey){
           document.getElementById('messagebox').submit();
       }
   },
   

but the reactJS is not capturing the form submit triggered by textareaKeypress. How can I call the sendMessage from textareaKeypress with proper event?

Answer 1

I learned something new today: this is just how the DOM works.

From the MDN site:

The form's onsubmit event handler (for example, onsubmit="return false;") will not be triggered when invoking this method from Gecko-based applications. In general, it is not guaranteed to be invoked by HTML user agents.

According to the HTML spec:

The submit() method, when invoked, must submit the form element from the form element itself, with the submitted from submit() method flag set.

followed by (section 4.10.22.3)

If the submitted from submit() method flag is not set, then fire a simple event that bubbles and is cancelable named submit, at form.

So, the event is not fired if the submit() method flag is set.

---

I was able to get the behavior you (and I) were expecting via the following code (JSFiddle example):

<form onSubmit={this.handleSubmit} ref="form">
  <textarea onKeyPress={this.handleKeyPress} />
</form>

// ...

this.refs.form.getDOMNode().dispatchEvent(new Event("submit"));

(You'll need more verbose code in IE.)

jQuery's $(form).submit() delegates to $(form).trigger("submit"), so I expect it's a similar workaround.

Answer 2

It's your component, so you don't need to worry about passing actual events around. You have some event handlers, and then you have the actual action.

sendMessage: function(){
    console.log('message:', this.state.message);
},
handleFormSubmit: function(event){
    event.preventDefault();
    this.sendMessage();
},
handleTextareaKeypress: function(event){
    if (event.which == 13 && !event.shiftKey){
        this.sendMessage();
    }
}