html - Use SED to extract value of all input elements with a certain name

Question

Welcome To Ask or Share your Answers For Others

html - Use SED to extract value of all input elements with a certain name

posted Jan 31, 2022 in Technique[技术] by 深蓝 (71.8m points)

html - Use SED to extract value of all input elements with a certain name

How do I get the value attribute based on a search of some other attribute?

For example:

<body>
<input name="dummy" value="foo">
<input name="alpha" value="bar">
</body>

How do I get the value of the input element with the name "dummy"?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙；凝视深渊过久,深渊将回以凝视…

1 Reply

深蓝 · Answer 1 · 2022-01-31T07:21:23+0000

Since you're asking for SED, I'll assume you want a command line option. However, a tool built for html parsing may be more effective. The problem with my first answer is that I don't know of a way in css to select the value of an attribute (does anyone else?). However, with xml you can select attributes like you could other elements. Here is a command line option for using an xml parsing tool.

Treat it as XML; use XPATH

Install xmlstarlet with your package manager
Run xmlstarlet sel -t -v //input[@name='dummy']/@value example.html (where example.html contains your html
If your html isn't valid xml, follow the warnings from xmlstarlet to make the necessary changes (in this case, <input> must be changed to <input/>
Run the command again. Returns: foo

why you might/might not use this approach

it is way more simple and robust than hand-rolling a regex html parser, but
it requires well formed html

Categories

html - Use SED to extract value of all input elements with a certain name

html - Use SED to extract value of all input elements with a certain name

Please log in or register to add a comment.

Please log in or register to reply this article.

1 Reply

Treat it as XML; use XPATH

why you might/might not use this approach

Please log in or register to add a comment.

Just Browsing Browsing

Most popular tags