Javascript 根据条件选择和显示值

我有下面的XML，在这里我删除了很多属性和数据以使它更简单

<isoColumns TYPE="string" SID="175" NORDERBY="6" NULLABLE="N" MAXLENGTH="65" ISKEY="N" COLNAME="IN_RELATION_ACTIVITY" LABEL="Where" INFORM="Y" INQUERY="N" CATEGORY="1" ISOCID="251319" LINEFEED="X" />

<isoColumns TYPE="date" SID="175" NORDERBY="7" NULLABLE="N" MAXLENGTH="10" ISKEY="N" COLNAME="DATE_" LABEL="Date" INFORM="Y" INQUERY="N" CATEGORY="1" ISOCID="251325" LINEFEED="X" GROUPID="251315" TXTHEAD="Baseline data"/>

<isoColumns TYPE="date" SID="175" NORDERBY="9" NULLABLE="Y" MAXLENGTH="10" ISKEY="N" COLNAME="DATE_OF_LASTCHANGE" LABEL="last change" INFORM="N" INQUERY="N" CATEGORY="2" ISOCID="606525" />

<isoColumns TYPE="date" SID="175" NORDERBY="10" NULLABLE="N" MAXLENGTH="10" ISKEY="N" COLNAME="DATE_OF_REPORT" LABEL="report" INFORM="Y" INQUERY="N" CATEGORY="2" ISOCID="251331" LINEFEED="X" "/>

<isoColumns TYPE="time" SID="175" NORDERBY="11" NULLABLE="Y" MAXLENGTH="15" ISKEY="N" COLNAME="DATE_OF_REPORT" LABEL="Time" INFORM="Y" INQUERY="N" CATEGORY="0" ISOCID="251179" LINEFEED="X"/>

<isoColumns TYPE="string" SID="175" NORDERBY="12" NULLABLE="Y" MAXLENGTH="20" ISKEY="N" COLNAME="USER_" LABEL="last change" INFORM="Y" INQUERY="N" CATEGORY="2" ISOCID="251315" />

<isoColumns TYPE="string" SID="175" NORDERBY="13" NULLABLE="Y" MAXLENGTH="35" ISKEY="N" COLNAME="PLACE_FOR_SAR" LABEL="Country" INFORM="Y" INQUERY="N" CATEGORY="1" ISOCID="251332" LINEFEED="X"  GROUPID="251243" TXTHEAD="Place for SAE/SAR"/>

<isoColumns TYPE="string" SID="175" NORDERBY="14" NULLABLE="Y" MAXLENGTH="35" ISKEY="N" COLNAME="CENTER_FOR_SAR" LABEL="Center" INFORM="Y" INQUERY="N" CATEGORY="1" ISOCID="251333" />

我想做几件事

如果

isoColumns

有一个名为

TXTHEAD

的属性，我想打印它的值。如上所述，一个

isoColumn

具有

TXTHEAD=“基线数据”

。我想打印

基线数据

这是我用以下代码尝试的内容：

     obj.forEach(function (n) { 
    if(xpath.select("../../*[@TXTHEAD]",n)) { <--- Trying to check if attribute "TXTHEAD" exists
       var test = ""+xpath.select("../../@TXTHEAD",n);
       console.log(test.value);              
 }

说清楚。。。当我编写一个等列时，我的意思是这样的（这是我们在XML中看到的许多内容）：

---

我不完全确定第2部分的内容，但以下内容至少可以让您接近我认为您需要的内容：

let DOMParser = require('xmldom').DOMParser
 , xpath = require('xpath') 
 , XMLSerializer = require('xmldom').XMLSerializer;

# for part 1
let th = xpath.select("//isoColumns[@TXTHEAD]/@TXTHEAD", root);
for (let t of th) { 
    target = xpath.select('.//*/@*',t)
    console.log(t.nodeValue);
};

# for part 2
let gi = xpath.select("//isoColumns[@GROUPID]", root);
myArray =[];
for (let g of gi){
        gid = xpath.select("./@GROUPID",g)[0].nodeValue;
        targets = xpath.select(".//following-sibling::*",g);           
        for (let target of targets) {    
                let serializedXML = new XMLSerializer().serializeToString(target);                       
                myArray.push(serializedXML);                     
                iid = xpath.select("./@ISOCID",target)[0].nodeValue                       
                if(iid === gid) {                           
                    for (let r of myArray){
                        console.log(r)};
                    return; 
                }                         
            };                   
};

输出：

Baseline data
Place for SAE/SAR

<isoColumns TYPE="date" SID="175" NORDERBY="9" NULLABLE="Y" MAXLENGTH="10" ISKEY="N" COLNAME="DATE_OF_LASTCHANGE" LABEL="last change" INFORM="N" INQUERY="N" CATEGORY="2" ISOCID="606525"/>
<isoColumns TYPE="date" SID="175" NORDERBY="10" NULLABLE="N" MAXLENGTH="10" ISKEY="N" COLNAME="DATE_OF_REPORT" LABEL="report" INFORM="Y" INQUERY="N" CATEGORY="2" ISOCID="251331" LINEFEED="X"/>
<isoColumns TYPE="time" SID="175" NORDERBY="11" NULLABLE="Y" MAXLENGTH="15" ISKEY="N" COLNAME="DATE_OF_REPORT" LABEL="Time" INFORM="Y" INQUERY="N" CATEGORY="0" ISOCID="251179" LINEFEED="X"/>
<isoColumns TYPE="string" SID="175" NORDERBY="12" NULLABLE="Y" MAXLENGTH="20" ISKEY="N" COLNAME="USER_" LABEL="last change" INFORM="Y" INQUERY="N" CATEGORY="2" ISOCID="251315"/>

基线数据
SAE/SAR的地点

问题的第2部分不清楚：鉴于问题中的xml，您能否编辑您的问题并添加预期的输出？非常感谢，这正是我所需要的。我注意到您使用let而不是var。这只是个人偏好吗？@user1960836很高兴它起作用了！使用let主要是个人偏好，尽管两者之间存在差异。。

<isoColumns TYPE="date" SID="175" NORDERBY="7" NULLABLE="N" MAXLENGTH="10" ISKEY="N" COLNAME="DATE_" LABEL="Date" INFORM="Y" INQUERY="N" CATEGORY="1" ISOCID="251325" LINEFEED="X" GROUPID="251315" TXTHEAD="Baseline data"/>

let DOMParser = require('xmldom').DOMParser
 , xpath = require('xpath') 
 , XMLSerializer = require('xmldom').XMLSerializer;

# for part 1
let th = xpath.select("//isoColumns[@TXTHEAD]/@TXTHEAD", root);
for (let t of th) { 
    target = xpath.select('.//*/@*',t)
    console.log(t.nodeValue);
};

# for part 2
let gi = xpath.select("//isoColumns[@GROUPID]", root);
myArray =[];
for (let g of gi){
        gid = xpath.select("./@GROUPID",g)[0].nodeValue;
        targets = xpath.select(".//following-sibling::*",g);           
        for (let target of targets) {    
                let serializedXML = new XMLSerializer().serializeToString(target);                       
                myArray.push(serializedXML);                     
                iid = xpath.select("./@ISOCID",target)[0].nodeValue                       
                if(iid === gid) {                           
                    for (let r of myArray){
                        console.log(r)};
                    return; 
                }                         
            };                   
};

Baseline data
Place for SAE/SAR

<isoColumns TYPE="date" SID="175" NORDERBY="9" NULLABLE="Y" MAXLENGTH="10" ISKEY="N" COLNAME="DATE_OF_LASTCHANGE" LABEL="last change" INFORM="N" INQUERY="N" CATEGORY="2" ISOCID="606525"/>
<isoColumns TYPE="date" SID="175" NORDERBY="10" NULLABLE="N" MAXLENGTH="10" ISKEY="N" COLNAME="DATE_OF_REPORT" LABEL="report" INFORM="Y" INQUERY="N" CATEGORY="2" ISOCID="251331" LINEFEED="X"/>
<isoColumns TYPE="time" SID="175" NORDERBY="11" NULLABLE="Y" MAXLENGTH="15" ISKEY="N" COLNAME="DATE_OF_REPORT" LABEL="Time" INFORM="Y" INQUERY="N" CATEGORY="0" ISOCID="251179" LINEFEED="X"/>
<isoColumns TYPE="string" SID="175" NORDERBY="12" NULLABLE="Y" MAXLENGTH="20" ISKEY="N" COLNAME="USER_" LABEL="last change" INFORM="Y" INQUERY="N" CATEGORY="2" ISOCID="251315"/>