React.js-REF未定义

Question

When I test the following code I receive a console error that newText is undefined, am I declaring the val var correctly or am I missing something?

val = ReactDOM.findDOMNode(this.refs[newText]);

renderForm: function() {
        return (
            <div className="note">
                <textarea ref="newText" defaultValue={this.props.children} className="form-control"></textarea>
                <button onClick={this.save} className="btn btn-success btn-sm glyphicon glyphicon-floppy-disk"></button>
            </div>
        )
    },

Answer 1

newText here needs to be either a string ( "newText" ) or should use dot notation instead. Using just newText means you're trying to read the value of a variable with that name (which will return undefined ).

Change:

this.refs[newText]

To:

this.refs["newText"]

Or:

this.refs.newText

Answer 2

I know it's very late to answer this but I came across the same problem.

I added and update the following sources: src= " https://unpkg.com/react@15/dist/react.js "> src="https://unpkg.com/react-dom@15/dist/react-dom.js">

It worked for me.

Hope you already found a solution for this. Cheers!

Answer 3

使用this.refs.newText而不是this.refs[newText] 。