![start(), then(), run(), exit()
start()
Signature: start(String url [, Function then])
Configures and starts Casper, then open the provided url and optionally adds the step provided by the then argument
then()
Signature: then(Function then)
run()
Signature: run(fn onComplete[, int time])
Runs the whole suite of steps and optionally executes a callback when they’ve all been done. Obviously, calling this method is
mandatory in order to run the Casper navigation suite.
exit()
Signature: exit([int status])
Exits PhantomJS with an optional exit status code.
Note that the current Casper instance automatically binds the this keyword for you within step functions](https://image.slidesharecdn.com/casperjs-131229222754-phpapp01/85/CasperJS-7-320.jpg)
![casper module – fill
Signature: fill(String selector, Object values[, Boolean submit])
Fills the fields of a form with given values and optionally submits it.
Fields are referenced by their name attribute.](https://image.slidesharecdn.com/casperjs-131229222754-phpapp01/85/CasperJS-10-320.jpg)
![evaluate
Signature: evaluate(Function fn[, arg1[, arg2[, …]]])
Evaluates an expression in the current page DOM context](https://image.slidesharecdn.com/casperjs-131229222754-phpapp01/85/CasperJS-12-320.jpg)
![waitForSelector
Signature: waitForSelector(String selector[, Function then, Function onTimeout, Number
timeout])
Waits until an element matching the provided selector expression exists in remote DOM to
process any next step](https://image.slidesharecdn.com/casperjs-131229222754-phpapp01/85/CasperJS-14-320.jpg)
CasperJS
- 2. CasperJS CasperJS is an open source navigation scripting & testing utility written in Javascript for the PhantomJS WebKit headless browser and SlimerJS (Gecko). It eases the process of defining a full navigation scenario and provides useful high-level functions, methods & syntactic sugar
- 3. Doing common tasks such as: defining & ordering browsing navigation steps filling & submitting forms clicking & following links capturing screenshots of a page (or part of it) testing remote DOM logging events downloading resources, including binary ones writing functional test suites, saving results as JUnit XML scraping Web contents
- 4. Installation Prerequisites PhantomJS PhantomJS is a headless WebKit scriptable with a JavaScript API. It has fast and native support for various web standards: DOM handling, CSS selector, JSON, Canvas, and SVG. http://phantomjs.org/download.html CasperJS
- 5. 目標 列舉出目前 IPTECH TW 的目前可檢索的站台
- 6. A minimal scraping script What did we just do? we created a new Casper instance we started it and opened http://casperjs.org/ once the page has been loaded, we asked to print the title of that webpage (the content of its <title> tag) then we opened another url, http://phantomjs.org/ once the new page has been loaded, we asked to print its title too we executed the whole process
- 7. start(), then(), run(), exit() start() Signature: start(String url [, Function then]) Configures and starts Casper, then open the provided url and optionally adds the step provided by the then argument then() Signature: then(Function then) run() Signature: run(fn onComplete[, int time]) Runs the whole suite of steps and optionally executes a callback when they’ve all been done. Obviously, calling this method is mandatory in order to run the Casper navigation suite. exit() Signature: exit([int status]) Exits PhantomJS with an optional exit status code. Note that the current Casper instance automatically binds the this keyword for you within step functions
- 8. start(), then(), run(), exit()
- 9. start(), then(), run(), exit() ?
- 10. casper module – fill Signature: fill(String selector, Object values[, Boolean submit]) Fills the fields of a form with given values and optionally submits it. Fields are referenced by their name attribute.
- 11. click click(Number x, Number y) click(String selector) Performs a click on the first element found matching the provided selector expression or at given coordinates if two numbers are passed selector expression CSS3 selector strings Xpath expressions
- 12. evaluate Signature: evaluate(Function fn[, arg1[, arg2[, …]]]) Evaluates an expression in the current page DOM context
- 13. Understanding evaluate() Think of the evaluate() method as a gate between the CasperJS environment and the one of the page you have opened; Every time you pass a closure to evaluate(), you’re entering the page and execute code as if you were using the browser console.
- 14. waitForSelector Signature: waitForSelector(String selector[, Function then, Function onTimeout, Number timeout]) Waits until an element matching the provided selector expression exists in remote DOM to process any next step
- 15. references http://docs.casperjs.org/en/latest/quickstart.html http://docs.casperjs.org/en/latest/modules/index.html http://docs.casperjs.org/en/latest/modules/casper.html#start http://docs.casperjs.org/en/latest/modules/casper.html#then http://docs.casperjs.org/en/latest/modules/casper.html#run http://docs.casperjs.org/en/latest/modules/casper.html#exit http://docs.casperjs.org/en/latest/modules/casper.html#fill http://docs.casperjs.org/en/latest/selectors.html http://docs.casperjs.org/en/latest/modules/mouse.html#click