页面关键字高亮

keywordHighlight.js

//关键字从页面的 url 获取；譬如： www.yourwebsite.com?p=1234
var keyword = window.location.search.substr(3);
keyword = decodeURIComponent(keyword);
    /**
    *   页面高亮关键字
    *   @param {string} targetNode: 要进行高亮的范围节点，需要类名（不需要加.）。
    *   @param {string} keyword: 高亮的关键字
    *   @param {array} exclude: 要排除的节点名字数组
    */
    function HighLight(targetNode, keyword, excludeArr) {
        this.targetNode = targetNode;
        this.keyword = keyword;
        this.excludeArr = excludeArr;
        this._init();
    };

    HighLight.prototype = {
        constructor: HighLight,
        _init: function() {
            this._addHightLightClass();
        },
        _getNode: function() {
            var node = document.body;
            var targetNode = this.targetNode;
            var result = null;
            for (var i = 0, j = node.childNodes.length; i < j; i++) {
                if (node.childNodes[i].className === targetNode) {
                    result = node.childNodes[i];
                    break;
                }
            }
            return result;
        },
        _addHightLightClass: function(node) {
            if (!node) {
                node = this._getNode();
            }
            var keyword = this.keyword;
            var excludeArr = this.excludeArr;
            for (var i = 0; i < node.childNodes.length; i++) {
                var childNode = node.childNodes[i];
                var textValue = childNode.nodeValue;
                if (excludeArr.indexOf(childNode.className) > -1) {
                    continue;
                } else {
                    if (textValue && this._trim(textValue).length && textValue.indexOf(keyword) > -1) {
                        var re = new RegExp('(' + keyword + ')','g');
                        var newStr = '<span class="highlight">' + keyword +'</span>';
                        var newNodeValue = textValue.replace(re, newStr);
                        childNode.parentNode.innerHTML = newNodeValue;
                    } else {
                        this._addHightLightClass(childNode);
                    }
                }

            }
        },
        _trim: function(string, chars, guard) {
            var reTrim = /^\s+|\s+$/g;
            if (!string) {
                return string;
            }
            if (guard || chars === undefined) {
                return string.replace(reTrim, '');
            }
            chars = (chars + '');
            if (!chars) {
                return string;
            }
        }

    }