classSet()
is a neat utility for easily manipulating the DOM class
string.
Here's a common scenario and its solution without classSet()
:
// inside some `<Message />` React component
render: function() {
var classString = 'message';
if (this.props.isImportant) {
classString += ' message-important';
}
if (this.props.isRead) {
classString += ' message-read';
}
// 'message message-important message-read'
return <div className={classString}>Great, I'll be there.</div>;
}
This can quickly get tedious, as assigning class name strings can be hard to read and error-prone. classSet()
solves this problem:
render: function() {
var cx = React.addons.classSet;
var classes = cx({
'message': true,
'message-important': this.props.isImportant,
'message-read': this.props.isRead
});
// same final string, but much cleaner
return <div className={classes}>Great, I'll be there.</div>;
}
When using classSet()
, pass an object with keys of the CSS class names you might or might not need. Truthy values will result in the key being a part of the resulting string.
No more hacky string concatenations!