45 lines
2.0 KiB
Markdown
45 lines
2.0 KiB
Markdown
**English** | [Dansk](Lecture-Steps-da) | [Bahasa Malaysia](Lecture-Steps-ms)
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# Lecture steps
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## Step 1 - Open the page
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`driver.get("https://www.python.org/")` loads the page in Chrome.
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**What you gain:** the driver is your remote control for a real browser. It
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must always be closed again, so the modern code wraps it in `try/finally`.
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## Step 2 - Locate the widget with the inspector
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Right-click the widget and choose *Inspect*. The events live inside an element
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with the class `event-widget`; each event is an `li` holding a `time` and an
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`a` tag.
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**What you gain:** you learn to read the HTML tree and find the container that
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holds exactly the data you want.
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## Step 3 - Select the five list items with a CSS selector
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`driver.find_elements(By.CSS_SELECTOR, ".event-widget li")` returns the five
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items. A class-based selector is shorter and more stable than the long XPath
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copied from the inspector, and it does not match unrelated links.
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**What you gain:** you know the Selenium locator strategies and when CSS
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selectors beat XPath.
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## Step 4 - Build the dictionary
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For every item we read `time` and `a` and store them under the item's index,
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with `enumerate` instead of a manual counter.
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**What you gain:** you turn page elements into structured data: a dictionary
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of dictionaries, ready to use in the rest of a program.
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