Come si usa jQuery in CasperJS?

Question

casper.start(URL, function() { 

    casper.page.injectJs('C:/Users/Mike/Documents/n1k0-casperjs-bc0da16/jquery-1.10.2.min.js'); 
    var names = $('span.author-name'); 
    this.echo(names); 
    this.exit(); 
} 

ReferenceError: Non riesci a trovare variabile: $

Cosa devo fare? Ho provato anche questo quando si crea l'istanza Casper:

var casper = require('casper').create({ 

    // I've tried both commented lines below 

    // clientScripts: ['C:/Users/Mike/Documents/n1k0-casperjs-bc0da16/jquery-1.10.2.min.js'] 
    // clientScripts: ['includes/jquery-1.10.2.min.js'] 
}); 

Answer 1

Dovete valutare il codice jQuery nel contesto del browser utilizzando casper.evaluate

execute code as if you were using the browser console.

var nameCount = this.evaluate(function() { 
    var names = $('span.author-name') 
    return names.length; 
}); 
this.echo(nameCount);