using System;
using System.IO;
using System.Text;
using System.Xml;
using NewLife.Log;
namespace NewLife.Configuration
{
/// <summary>Xml文件配置提供者</summary>
/// <remarks>
/// 支持从不同配置文件加载到不同配置模型
/// </remarks>
public class XmlConfigProvider : FileConfigProvider
{
/// <summary>根元素名称</summary>
public String RootName { get; set; } = "Root";
/// <summary>初始化</summary>
/// <param name="value"></param>
public override void Init(String value)
{
if ((RootName.IsNullOrEmpty() || RootName == "Root") && !value.IsNullOrEmpty()) RootName = Path.GetFileNameWithoutExtension(value);
// 加上默认后缀
if (!value.IsNullOrEmpty() && Path.GetExtension(value).IsNullOrEmpty()) value += ".config";
base.Init(value);
}
/// <summary>读取配置文件</summary>
/// <param name="fileName">文件名</param>
/// <param name="section">配置段</param>
protected override void OnRead(String fileName, IConfigSection section)
{
using var fs = File.OpenRead(fileName);
using var reader = XmlReader.Create(fs);
// 移动到第一个元素
while (reader.NodeType != XmlNodeType.Element) reader.Read();
if (!reader.Name.IsNullOrEmpty()) RootName = reader.Name;
reader.ReadStartElement();
while (reader.NodeType == XmlNodeType.Whitespace) reader.Skip();
ReadNode(reader, section);
if (reader.NodeType == XmlNodeType.EndElement) reader.ReadEndElement();
}
private void ReadNode(XmlReader reader, IConfigSection section)
{
while (true)
{
var remark = "";
if (reader.NodeType == XmlNodeType.Comment) remark = reader.Value;
while (reader.NodeType == XmlNodeType.Comment || reader.NodeType == XmlNodeType.Whitespace) reader.Skip();
if (reader.NodeType != XmlNodeType.Element) break;
var name = reader.Name;
var cfg = section.GetOrAddChild(name);
// 前一行是注释
if (!remark.IsNullOrEmpty()) cfg.Comment = remark;
reader.ReadStartElement();
while (reader.NodeType == XmlNodeType.Whitespace) reader.Skip();
// 遇到下一层节点
if (reader.NodeType == XmlNodeType.Element || reader.NodeType == XmlNodeType.Comment)
ReadNode(reader, cfg);
else if (reader.NodeType == XmlNodeType.Text)
cfg.Value = reader.ReadContentAsString();
if (reader.NodeType == XmlNodeType.Attribute) reader.Read();
if (reader.NodeType == XmlNodeType.EndElement) reader.ReadEndElement();
while (reader.NodeType == XmlNodeType.Whitespace) reader.Skip();
}
}
/// <summary>写入配置文件</summary>
/// <param name="fileName">文件名</param>
/// <param name="section">配置段</param>
protected override void OnWrite(String fileName, IConfigSection section)
{
var str = GetString(section);
var old = "";
if (File.Exists(fileName)) old = File.ReadAllText(fileName);
if (str != old)
{
XTrace.WriteLine("保存配置 {0}", fileName);
File.WriteAllText(fileName, str);
}
}
/// <summary>获取字符串形式</summary>
/// <param name="section">配置段</param>
/// <returns></returns>
public override String GetString(IConfigSection section = null)
{
if (section == null) section = Root;
var set = new XmlWriterSettings
{
Encoding = Encoding.UTF8,
Indent = true,
CloseOutput = true,
};
using var ms = new MemoryStream();
using var writer = XmlWriter.Create(ms, set);
writer.WriteStartDocument();
WriteNode(writer, RootName, section);
writer.WriteEndDocument();
writer.Flush();
ms.Position = 0;
return ms.ToStr();
}
private void WriteNode(XmlWriter writer, String name, IConfigSection section)
{
writer.WriteStartElement(name);
foreach (var item in section.Childs)
{
// 写注释
if (!item.Comment.IsNullOrEmpty()) writer.WriteComment(item.Comment);
if (item.Childs != null)
WriteNode(writer, item.Key, item);
else
{
// 避免写null时导致xml元素未闭合
writer.WriteStartElement(item.Key);
writer.WriteValue(item.Value + "");
writer.WriteEndElement();
}
}
writer.WriteEndElement();
}
}
}
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