如何使用正则表达式删除一些 CSS 属性？

Question

"outline-style: none; margin: 0px; padding: 2px; background-color: #eff0f8; color: #3b3a39; font-family: Georgia,'Times New Roman',Times,serif; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: 18px; orphans: 2; text-align: center; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border: 1px solid #ebebeb; float: left;"

我有这个作为内联 css。我想用正则表达式替换所有以“背景”和“字体”开头的属性。在 inline css 中，最后一个属性可能没有分号作为结尾

我将此代码用作 django 过滤器，以使用漂亮的汤从服务器端删除这些属性

def html_remove_attrs(value):
    soup = BeautifulSoup(value)
    print "hi"
    for tag in soup.findAll(True,{'style': re.compile(r'')}): 
        #tag.attrs = None
        #for attr in tag.attrs:
        #    if "class" in attr:
        #        tag.attrs.remove(attr)
        #    if "style" in attr:
        #        tag.attrs.remove(attr)
        for attr in tag.attrs:
            if "style" in attr:
                #remove the background and font properties 

    return soup

Answer 1

我不知道你的编程环境的细节，但你要求一个正则表达式。此正则表达式将查找属性键（加上冒号和任何空格）作为第 1 组 ($1) 并将属性值作为第 2 组 ($2)：

 ((?:background|font)(?:[^:]+):(?:\\s*))([^;]+)

表达式不会删除属性值。它找到了它们。如何删除它们取决于您的编程环境（语言/库）。

但基本上，您将进行全局查找/替换，将整个结果替换为 $1。

例如，使用 Java 你可以做到这一点

public static void main(String[] args) throws Exception {

    String[] lines = {
        "outline-style: none; margin: 0px; padding: 2px; background-color: #eff0f8; color: #3b3a39; font-family: Georgia,'Times New Roman',Times,serif; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: 18px; orphans: 2; text-align: center; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border: 1px solid #ebebeb; float: left;",
        "outline-style: none; margin: 0px; padding: 2px; background-color: #eff0f8; color: #3b3a39; font-family: Georgia,'Times New Roman',Times,serif; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: 18px; orphans: 2; text-align: center; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border: 1px solid #ebebeb; float: left",
        "background-color: #eff0f8;",
        "background-color: #eff0f8",
    };

    String regex = "((?:background|font)(?:[^:]+):(?:\\s*))([^;]+)";

    Pattern p = Pattern.compile(regex);

    for (String s: lines) {
        StringBuffer sb = new StringBuffer();
        Matcher m = p.matcher(s);
        while (m.find()) {

            // capturing group(2) for debug purpose only
            // just to get it's length so we can fill that with '-' 
            // to assist comparison of before and after
            String text = m.group(2);
            text = text.replaceAll(".", "-");
            m.appendReplacement(sb, "$1"+text);

            // for non-debug mode, just use this instead
            // m.appendReplacement(sb, "$1");
        }
        m.appendTail(sb);

        System.err.println("> " + s); // before
        System.err.println("< " +sb.toString()); // after
        System.err.println();
    }
}