Question

我想在C＃中使用XmlWriter类生成以下格式的XML：

<?xml version="1.0" ?>
<root>
 <data>
  <entry Attrib1="" Attrib2="91.3467" Attrib3="95.3052" Attrib4="6.4722" />
  <entry Attrib1="" Attrib2="91.3467" Attrib3="95.3052" Attrib4="6.4722" />
 </data>
</root>

我对XmlWriter类和C＃一般都是新手，我尝试编写用于生成具有上述格式的文件的代码，但该尝试不成功

var xmlWriter = XmlWriter.Create(filename);
    xmlWriter.WriteStartDocument();
    xmlWriter.WriteStartElement("data");

    xmlWriter.WriteStartElement("entry");
    xmlWriter.WriteAttributeString("attrib1", "value1");
    xmlWriter.WriteAttributeString("attrib2", "value2");
    xmlWriter.Close();

另外，属性的名称可以包含非法的XML字符，这就是我阅读XMLWriter的原因，因为它似乎从属性的名称中删除了那些非法字符，例如“this is attribute”这样的名称在写入生成的XML时，应将“1”简化为类似“this_is_attribute_1”的内容，如何使用XML生成此类XmlWriter。简而言之，生成的XML行就像这样

<entry P_B_Pe="" P_E_Pe="91.3467" Custom_Price="95.3052" C_Yield="6.4722" Average_Life="" />

Answer 1

你几乎得到了它......

var xmlWriter = XmlWriter.Create(filename);
    xmlWriter.WriteStartDocument();
        xmlWriter.WriteStartElement("root");
            xmlWriter.WriteStartElement("data");
                xmlWriter.WriteStartElement("entry");
                    xmlWriter.WriteAttributeString("attrib1", "value1");
                    xmlWriter.WriteAttributeString("attrib2", "value2");
                xmlWriter.WriteEndElement(); // entry
                xmlWriter.WriteStartElement("entry");
                    xmlWriter.WriteAttributeString("attrib1", "value1");
                    xmlWriter.WriteAttributeString("attrib2", "value2");
                xmlWriter.WriteEndElement(); // entry
            xmlWriter.WriteEndElement(); // data
        xmlWriter.WriteEndElement(); // root
    xmlWriter.WriteEndDocument();
xmlWriter.Close();

默认情况下，XmlWriter将对原始数据或属性值中通常无效的字符进行编码，以便在使用读取器解码XML时它们会返回，但属性和元素名称仍然必须有效。如果你想以某种特殊的方式处理那些与之不同的无效字符，你需要根据你想要建立的规则自己做这些，例如：

xmlWriter.WriteAttributeString(MyXmlExtensions.EncodeXmlAttributeName("this is normally an invalid attribute name"), "value1");

class MyXmlExtensions
{
    public string EncodeXmlAttributeName(string decoded)
    {
        // not that you'll likely need to enhance this with whatever rules you want but haven't specified
        return decoded.Replace(" ", "_");
    }
    public string DecodeXmlAttributeName(string encoded)
    {
        // not that you'll likely need to enhance this with whatever rules you want but haven't specified
        return encoded.Replace("_", " ");
    }
}

如果您希望输出看起来很漂亮（标签，多行等），您还需要在XmlWriterSettings的调用中使用XmlWriter.Create。

Answer 2

尝试XML Linq

<button type="button" class="btn btn-primary" ng-click="ctrl.changeDisplay()">Save Add Another</button>

然后没有任何xml linq

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml;
using System.Xml.Linq;
using System.IO;

namespace ConsoleApplication1
{
    class Program
    {
        const string FILENAME = @"c:\temp\test.xml";
        static void Main(string[] args)
        {
            StreamWriter sWriter = new StreamWriter(FILENAME);
            XmlTextWriter writer = new XmlTextWriter(sWriter);

            writer.WriteStartDocument();
            writer.WriteStartElement("root");
            writer.WriteStartElement("data");

            double?[] attributes = new double?[] { null, 91.3467, 95.3052, 6.4722 };
            XElement entry = new XElement("entry");
            int index = 1;

            foreach (double? attribute in attributes)
            {
                if (attribute == null)
                {
                    entry.Add(new XAttribute("Attrib" + index++.ToString(), ""));
                }
                else
                {
                    entry.Add(new XAttribute("Attrib" + index++.ToString(), attribute));
                }
            }

            writer.WriteRaw(entry.ToString());
            writer.WriteRaw(entry.ToString());

            writer.WriteEndElement();
            writer.WriteEndElement();

            writer.Flush();
            writer.Close();


        }
    }
}

Answer 3

使用对象序列化，然后您不必拥有构造映射代码的对象

using System.Xml.Serialization;

...

[XmlRoot("root")]
public class Example {
    [XmlElement("data")]
    public Entries Entries { get; set; }
}

public class Entries : List<List<string>>, IXmlSerializable {

    public List<string> Attribs { get; set; }

    public System.Xml.Schema.XmlSchema GetSchema() { return null; }

    public void ReadXml(System.Xml.XmlReader reader) { reader.MoveToContent(); }

    public void WriteXml(System.Xml.XmlWriter writer) {
        foreach (var entry in this) {
            writer.WriteStartElement("entry", "");
            var label = 1;
            foreach (var attrib in entry) {
                writer.WriteAttributeString(string.Format("Attrib{0}", label), attrib);
                label++;
            }
            writer.WriteEndElement();
        }
    }
}

...

var xml = new XmlSerializer(typeof(Example), "");
xml.Serialize(stream, example);

如何在C＃中使用XmlWriter类生成以下Xml？

3 个答案: