使用正则表达式在不在锚中的页面上查找电话号码

ShadowRanger.. 5

不要使用正则表达式来解析HTML。使用HTML / DOM解析器获取文本节点（浏览器可以为您过滤文本，删除锚标记和所有文本太短而无法包含电话号码的文本），您可以直接检查文本。

例如，使用XPath（虽然有点丑陋，但是支持以大多数其他DOM方法不直接处理文本节点的方式）：

// This query finds all text nodes with at least 12 non-whitespace characters
// who are not direct children of an anchor tag
// Letting XPath apply basic filters dramatically reduces the number of elements
// you need to process (there are tons of short and/or pure whitespace text nodes
// in most DOMs)
var xpr = document.evaluate('descendant-or-self::text()[not(parent::A) and string-length(normalize-space(self::text())) >= 12]',
                            document.body, null, XPathResult.UNORDERED_NODE_SNAPSHOT_TYPE, null);
for (var i=0, len=xpr.snapshotLength; i < len; ++i) {
    var txt = xpr.snapshotItem(i);
    // Splits with grouping to preserve the text split on
    var numbers = txt.data.split(/([(]?\d{3}[)]?[(\s)?.-]\d{3}[\s.-]\d{4})/);
    // split will return at least three items on a hit, prefix, split match, and suffix
    if (numbers.length >= 3) {
        var parent = txt.parentNode; // Save parent before replacing child
        // Insert new elements before existing element; first element is just
        // text before first phone number
        parent.insertBefore(document.createTextNode(numbers[0]), txt);

        // Now explicitly create pairs of anchors and following text nodes
        for (var j = 1; j < numbers.length; j += 2) {
            // Operate in pairs; odd index is phone number, even is
            // text following that phone number
            var anc = document.createElement('a');
            anc.href = 'tel:' + numbers[j].replace(/\D+/g, '');
            anc.textContent = numbers[j];
            parent.insertBefore(anc, txt);
            parent.insertBefore(document.createTextNode(numbers[j+1]), txt);
        }
        // Remove original text node now that we've inserted all the
        // replacement elements and don't need it for positioning anymore
        parent.removeChild(txt);

        parent.normalize(); // Normalize whitespace after rebuilding
    }
}

作为记录，基本过滤器在大多数页面上都有很大帮助。例如，在此页面上，现在，如我所见（随用户，浏览器，浏览器扩展和脚本等的不同而有所不同），如果没有过滤器，则该查询的快照'descendant-or-self::text()'将包含1794个项目。省略由锚标记标记的文本，'descendant-or-self::text()[not(parent::A)]'将其降至1538，然后执行完整查询，以验证非空白内容的长度至少为十二个字符，从而将其降至87项。在性能上，将正则表达式应用于87个项是不合常规的更改，并且您不再需要使用不合适的工具来解析HTML。

不要使用正则表达式来解析HTML。使用HTML / DOM解析器获取文本节点（浏览器可以为您过滤文本，删除锚标记和所有文本太短而无法包含电话号码的文本），您可以直接检查文本。

例如，使用XPath（虽然有点丑陋，但是支持以大多数其他DOM方法不直接处理文本节点的方式）：

// This query finds all text nodes with at least 12 non-whitespace characters
// who are not direct children of an anchor tag
// Letting XPath apply basic filters dramatically reduces the number of elements
// you need to process (there are tons of short and/or pure whitespace text nodes
// in most DOMs)
var xpr = document.evaluate('descendant-or-self::text()[not(parent::A) and string-length(normalize-space(self::text())) >= 12]',
                            document.body, null, XPathResult.UNORDERED_NODE_SNAPSHOT_TYPE, null);
for (var i=0, len=xpr.snapshotLength; i < len; ++i) {
    var txt = xpr.snapshotItem(i);
    // Splits with grouping to preserve the text split on
    var numbers = txt.data.split(/([(]?\d{3}[)]?[(\s)?.-]\d{3}[\s.-]\d{4})/);
    // split will return at least three items on a hit, prefix, split match, and suffix
    if (numbers.length >= 3) {
        var parent = txt.parentNode; // Save parent before replacing child
        // Insert new elements before existing element; first element is just
        // text before first phone number
        parent.insertBefore(document.createTextNode(numbers[0]), txt);

        // Now explicitly create pairs of anchors and following text nodes
        for (var j = 1; j < numbers.length; j += 2) {
            // Operate in pairs; odd index is phone number, even is
            // text following that phone number
            var anc = document.createElement('a');
            anc.href = 'tel:' + numbers[j].replace(/\D+/g, '');
            anc.textContent = numbers[j];
            parent.insertBefore(anc, txt);
            parent.insertBefore(document.createTextNode(numbers[j+1]), txt);
        }
        // Remove original text node now that we've inserted all the
        // replacement elements and don't need it for positioning anymore
        parent.removeChild(txt);

        parent.normalize(); // Normalize whitespace after rebuilding
    }
}

作为记录，基本过滤器在大多数页面上都有很大帮助。例如，在此页面上，现在，如我所见（随用户，浏览器，浏览器扩展和脚本等的不同而有所不同），如果没有过滤器，则该查询的快照'descendant-or-self::text()'将包含1794个项目。省略由锚标记标记的文本，'descendant-or-self::text()[not(parent::A)]'将其降至1538，然后执行完整查询，以验证非空白内容的长度至少为十二个字符，从而将其降至87项。在性能上，将正则表达式应用于87个项是不合常规的更改，并且您不再需要使用不合适的工具来解析HTML。