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我正在使用此链接 (http://km0.la/js/mozXPath/) 提供的自定义 javascript 函数在 FireFox 中实现特定的 XML 功能。

这是代码:

// mozXPath
// Code licensed under Creative Commons Attribution-ShareAlike License 
// http://creativecommons.org/licenses/by-sa/2.5/
if( document.implementation.hasFeature("XPath", "3.0") ) {
    if( typeof XMLDocument == "undefined" ) { XMLDocument = Document; }
    XMLDocument.prototype.selectNodes = function(cXPathString, xNode) {
        if( !xNode ) { xNode = this; }
        var oNSResolver = this.createNSResolver(this.documentElement);
        var aItems = this.evaluate(cXPathString, xNode, oNSResolver, 
                     XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
        var aResult = [];
        for( var i = 0; i < aItems.snapshotLength; i++) {
            aResult[i] = aItems.snapshotItem(i);
        }
        return aResult;
    }
    XMLDocument.prototype.selectSingleNode = function(cXPathString, xNode) {
        if( !xNode ) { xNode = this; } 
        var xItems = this.selectNodes(cXPathString, xNode);
        if( xItems.length > 0 ){ return xItems[0]; }
        else{ return null; }
    }
    Element.prototype.selectNodes = function(cXPathString) {
        if(this.ownerDocument.selectNodes) { 
            return this.ownerDocument.selectNodes(cXPathString, this);
        }
        else { throw "For XML Elements Only"; }
    }
    Element.prototype.selectSingleNode = function(cXPathString) {   
        if(this.ownerDocument.selectSingleNode) {
            return this.ownerDocument.selectSingleNode(cXPathString, this);
        }
        else { throw "For XML Elements Only"; }
    }
}

假设 XML 对象已经定义并加载了 XML 内容,下面是一个如何访问名为“cd_rank”的 XML 标记的示例:

var cd_rank_XMLObj = XMLObj.selectSingleNode("cd_rank");

我想要做的是将属性“nodeTypedValue”添加到 selectSingleNode() 函数中,但我不知道该怎么做。在 Element.prototype.selectSingleNode 函数中,我尝试添加:

this.prototype.nodeTypedValue = this.textContent;

但是,它给了我一个错误,说它是未定义的。我什至尝试将它添加到函数之外,只是为了简化它并了解概念,它还说它是未定义的:

var XMLObj.selectSingleNode.prototype.nodeTypedValue = XMLObj.textContent;
alert(XMLObj.selectSingleNode("cd_rank").nodeTypedValue);

我想,基本上我想要做的是将原型属性添加到原型函数。但我需要一些帮助。如何添加“nodeTypedValue”以便编写“XMLObj.selectSingleNode(Path).nodeTypedValue”?

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1 回答 1

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好的,我想我想出了如何在函数中添加它,可能更多的是因为运气而不是逻辑:

Element.prototype.selectSingleNode = function(cXPathString){    
    if(this.ownerDocument.selectSingleNode) {
        var result = this.ownerDocument.selectSingleNode(cXPathString, this);
        if (result != null) {
            result.nodeTypedValue = result.textContent;
        }
        return result;
    }
    else{throw "For XML Elements Only";}
}
于 2011-10-17T18:04:26.207 回答