c#读取xml文件配置文件Winform及WebForm-Demo具体解释

我这里用Winform和WebForm两种为例说明怎样操作xml文档来作为配置文件进行读取操作。

1.新建一个类，命名为“SystemConfig.cs”。代码例如以下：

<span style="font-family:Microsoft YaHei;font-size:14px;">using System;
using System.Collections.Generic;
using System.Text;
using System.Xml;
using System.IO;

namespace ConfigMgrTest
{
    public class SystemConfig
    {
        #region"基本操作函数"
        /// <summary>
        /// 得到程序工作文件夹
        /// </summary>
        /// <returns></returns>
        private static string GetWorkDirectory()
        {
            try
            {
                return Path.GetDirectoryName(typeof(SystemConfig).Assembly.Location);
            }
            catch
            {
                return System.Windows.Forms.Application.StartupPath;
            }
        }
        /// <summary>
        /// 推断字符串是否为空串
        /// </summary>
        /// <param name="szString">目标字符串</param>
        /// <returns>true:为空串;false:非空串</returns>
        private static bool IsEmptyString(string szString)
        {
            if (szString == null)
                return true;
            if (szString.Trim() == string.Empty)
                return true;
            return false;
        }
        /// <summary>
        /// 创建一个制定根节点名的XML文件
        /// </summary>
        /// <param name="szFileName">XML文件</param>
        /// <param name="szRootName">根节点名</param>
        /// <returns>bool</returns>
        private static bool CreateXmlFile(string szFileName, string szRootName)
        {
            if (szFileName == null || szFileName.Trim() == "")
                return false;
            if (szRootName == null || szRootName.Trim() == "")
                return false;

            XmlDocument clsXmlDoc = new XmlDocument();
            clsXmlDoc.AppendChild(clsXmlDoc.CreateXmlDeclaration("1.0", "GBK", null));
            clsXmlDoc.AppendChild(clsXmlDoc.CreateNode(XmlNodeType.Element, szRootName, ""));
            try
            {
                clsXmlDoc.Save(szFileName);
                return true;
            }
            catch
            {
                return false;
            }
        }

        /// <summary>
        /// 从XML文件获取相应的XML文档对象
        /// </summary>
        /// <param name="szXmlFile">XML文件</param>
        /// <returns>XML文档对象</returns>
        private static XmlDocument GetXmlDocument(string szXmlFile)
        {
            if (IsEmptyString(szXmlFile))
                return null;
            if (!File.Exists(szXmlFile))
                return null;
            XmlDocument clsXmlDoc = new XmlDocument();
            try
            {
                clsXmlDoc.Load(szXmlFile);
            }
            catch
            {
                return null;
            }
            return clsXmlDoc;
        }

        /// <summary>
        /// 将XML文档对象保存为XML文件
        /// </summary>
        /// <param name="clsXmlDoc">XML文档对象</param>
        /// <param name="szXmlFile">XML文件</param>
        /// <returns>bool:保存结果</returns>
        private static bool SaveXmlDocument(XmlDocument clsXmlDoc, string szXmlFile)
        {
            if (clsXmlDoc == null)
                return false;
            if (IsEmptyString(szXmlFile))
                return false;
            try
            {
                if (File.Exists(szXmlFile))
                    File.Delete(szXmlFile);
            }
            catch
            {
                return false;
            }
            try
            {
                clsXmlDoc.Save(szXmlFile);
            }
            catch
            {
                return false;
            }
            return true;
        }

        /// <summary>
        /// 获取XPath指向的单一XML节点
        /// </summary>
        /// <param name="clsRootNode">XPath所在的根节点</param>
        /// <param name="szXPath">XPath表达式</param>
        /// <returns>XmlNode</returns>
        private static XmlNode SelectXmlNode(XmlNode clsRootNode, string szXPath)
        {
            if (clsRootNode == null || IsEmptyString(szXPath))
                return null;
            try
            {
                return clsRootNode.SelectSingleNode(szXPath);
            }
            catch
            {
                return null;
            }
        }

        /// <summary>
        /// 获取XPath指向的XML节点集
        /// </summary>
        /// <param name="clsRootNode">XPath所在的根节点</param>
        /// <param name="szXPath">XPath表达式</param>
        /// <returns>XmlNodeList</returns>
        private static XmlNodeList SelectXmlNodes(XmlNode clsRootNode, string szXPath)
        {
            if (clsRootNode == null || IsEmptyString(szXPath))
                return null;
            try
            {
                return clsRootNode.SelectNodes(szXPath);
            }
            catch
            {
                return null;
            }
        }

        /// <summary>
        /// 创建一个XmlNode并加入到文档
        /// </summary>
        /// <param name="clsParentNode">父节点</param>
        /// <param name="szNodeName">结点名称</param>
        /// <returns>XmlNode</returns>
        private static XmlNode CreateXmlNode(XmlNode clsParentNode, string szNodeName)
        {
            try
            {
                XmlDocument clsXmlDoc = null;
                if (clsParentNode.GetType() != typeof(XmlDocument))
                    clsXmlDoc = clsParentNode.OwnerDocument;
                else
                    clsXmlDoc = clsParentNode as XmlDocument;
                XmlNode clsXmlNode = clsXmlDoc.CreateNode(XmlNodeType.Element, szNodeName, string.Empty);
                if (clsParentNode.GetType() == typeof(XmlDocument))
                {
                    clsXmlDoc.LastChild.AppendChild(clsXmlNode);
                }
                else
                {
                    clsParentNode.AppendChild(clsXmlNode);
                }
                return clsXmlNode;
            }
            catch
            {
                return null;
            }
        }

        /// <summary>
        /// 设置指定节点中指定属性的值
        /// </summary>
        /// <param name="parentNode">XML节点</param>
        /// <param name="szAttrName">属性名</param>
        /// <param name="szAttrValue">属性值</param>
        /// <returns>bool</returns>
        private static bool SetXmlAttr(XmlNode clsXmlNode, string szAttrName, string szAttrValue)
        {
            if (clsXmlNode == null)
                return false;
            if (IsEmptyString(szAttrName))
                return false;
            if (IsEmptyString(szAttrValue))
                szAttrValue = string.Empty;
            XmlAttribute clsAttrNode = clsXmlNode.Attributes.GetNamedItem(szAttrName) as XmlAttribute;
            if (clsAttrNode == null)
            {
                XmlDocument clsXmlDoc = clsXmlNode.OwnerDocument;
                if (clsXmlDoc == null)
                    return false;
                clsAttrNode = clsXmlDoc.CreateAttribute(szAttrName);
                clsXmlNode.Attributes.Append(clsAttrNode);
            }
            clsAttrNode.Value = szAttrValue;
            return true;
        }
        #endregion

        #region"配置文件的读取和写入"
        private static string CONFIG_FILE = "SystemConfig.xml";
        /// <summary>
        ///  读取指定的配置文件里指定Key的值
        /// </summary>
        /// <param name="szKeyName">读取的Key名称</param>
        /// <param name="szDefaultValue">指定的Key不存在时,返回的值</param>
        /// <returns>Key值</returns>
        public static int GetConfigData(string szKeyName, int nDefaultValue)
        {
            string szValue = GetConfigData(szKeyName, nDefaultValue.ToString());
            try
            {
                return int.Parse(szValue);
            }
            catch
            {
                return nDefaultValue;
            }
        }

        /// <summary>
        ///  读取指定的配置文件里指定Key的值
        /// </summary>
        /// <param name="szKeyName">读取的Key名称</param>
        /// <param name="szDefaultValue">指定的Key不存在时,返回的值</param>
        /// <returns>Key值</returns>
        public static float GetConfigData(string szKeyName, float fDefaultValue)
        {
            string szValue = GetConfigData(szKeyName, fDefaultValue.ToString());
            try
            {
                return float.Parse(szValue);
            }
            catch
            {
                return fDefaultValue;
            }
        }

        /// <summary>
        ///  读取指定的配置文件里指定Key的值
        /// </summary>
        /// <param name="szKeyName">读取的Key名称</param>
        /// <param name="szDefaultValue">指定的Key不存在时,返回的值</param>
        /// <returns>Key值</returns>
        public static bool GetConfigData(string szKeyName, bool bDefaultValue)
        {
            string szValue = GetConfigData(szKeyName, bDefaultValue.ToString());
            try
            {
                return bool.Parse(szValue);
            }
            catch
            {
                return bDefaultValue;
            }
        }

        /// <summary>
        ///  读取指定的配置文件里指定Key的值
        /// </summary>
        /// <param name="szKeyName">读取的Key名称</param>
        /// <param name="szDefaultValue">指定的Key不存在时,返回的值</param>
        /// <returns>Key值</returns>
        public static string GetConfigData(string szKeyName, string szDefaultValue)
        {
            string szConfigFile = string.Format("{0}\\{1}", GetWorkDirectory(), CONFIG_FILE);
            if (!File.Exists(szConfigFile))
            {
                return szDefaultValue;
            }

            XmlDocument clsXmlDoc = GetXmlDocument(szConfigFile);
            if (clsXmlDoc == null)
                return szDefaultValue;

            string szXPath = string.Format(".//key[@name='{0}']", szKeyName);
            XmlNode clsXmlNode = SelectXmlNode(clsXmlDoc, szXPath);
            if (clsXmlNode == null)
            {
                return szDefaultValue;
            }

            XmlNode clsValueAttr = clsXmlNode.Attributes.GetNamedItem("value");
            if (clsValueAttr == null)
                return szDefaultValue;
            return clsValueAttr.Value;
        }

        /// <summary>
        ///  保存指定Key的值到指定的配置文件里
        /// </summary>
        /// <param name="szKeyName">要被改动值的Key名称</param>
        /// <param name="szValue">新改动的值</param>
        public static bool WriteConfigData(string szKeyName, string szValue)
        {
            string szConfigFile = string.Format("{0}\\{1}", GetWorkDirectory(), CONFIG_FILE);
            if (!File.Exists(szConfigFile))
            {
                if (!CreateXmlFile(szConfigFile, "SystemConfig"))
                    return false;
            }
            XmlDocument clsXmlDoc = GetXmlDocument(szConfigFile);

            string szXPath = string.Format(".//key[@name='{0}']", szKeyName);
            XmlNode clsXmlNode = SelectXmlNode(clsXmlDoc, szXPath);
            if (clsXmlNode == null)
            {
                clsXmlNode = CreateXmlNode(clsXmlDoc, "key");
            }
            if (!SetXmlAttr(clsXmlNode, "name", szKeyName))
                return false;
            if (!SetXmlAttr(clsXmlNode, "value", szValue))
                return false;
            //
            return SaveXmlDocument(clsXmlDoc, szConfigFile);
        }
        #endregion
    }
}
</span>

PS：假设是Winform，则不用改动SystemConfig.cs的代码，假设是WebForm的话则需改动后面的路径和写入与读取的代码。将我标红框的删除就可以，如图：

2.WinForm的界面例如以下：

cs代码例如以下：

<pre name="code" class="csharp"><span style="font-family:Microsoft YaHei;font-size:14px;">using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace ConfigMgrTest
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
        }

        private void btnSave_Click(object sender, EventArgs e)
        {
            //保存
            SystemConfig.WriteConfigData("UserID", this.txtUserID.Text.Trim());
            SystemConfig.WriteConfigData("Password", this.txtPassword.Text.Trim());
            SystemConfig.WriteConfigData("Birthday",this.textBox3.Text.Trim());

            this.txtUserID.Text = null;
            this.txtPassword.Text = null;
            this.textBox3.Text = null;
            MessageBox.Show("成功保存到配置文件" + Application.StartupPath + "SystemConfig.xml \n点击读取button进行读取!");
        }

        private void btnClose_Click(object sender, EventArgs e)
        {
            //读取
            this.txtUserID.Text = SystemConfig.GetConfigData("UserID", string.Empty);
            this.txtPassword.Text = SystemConfig.GetConfigData("Password", string.Empty);
            this.textBox3.Text = SystemConfig.GetConfigData("Birthday", string.Empty);
        }

    }
}</span>

3.WebForm效果例如以下：

前台代码例如以下：

<span style="font-family:Microsoft YaHei;font-size:14px;"><%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="Tc.Web.WebForm1" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:Label ID="Label1" runat="server" Text="url1:"></asp:Label>
        <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>

    <p>
        <asp:Label ID="Label2" runat="server" Text="url2:"></asp:Label>
        <asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
    </p>
    <asp:Button ID="Button1" runat="server" Text="写入" onclick="Button1_Click" />
    <asp:Button ID="Button2" runat="server" Text="读取" onclick="Button2_Click" />
    </form>
    </div>
</body>
</html>
</span>

后台代码例如以下：

<span style="font-family:Microsoft YaHei;font-size:14px;">using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Tc.Web._Code;

namespace Tc.Web
{
    public partial class WebForm1 : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        protected void Button2_Click(object sender, EventArgs e)
        {
            //读取
            this.TextBox1.Text = SystemConfig.GetConfigData("url1", string.Empty);
            this.TextBox2.Text = SystemConfig.GetConfigData("url2", string.Empty);
        }

        protected void Button1_Click(object sender, EventArgs e)
        {
            //写入
            SystemConfig.WriteConfigData("url1", this.TextBox1.Text.Trim());
            SystemConfig.WriteConfigData("url2", this.TextBox2.Text.Trim());
            this.TextBox1.Text = null;
            this.TextBox2.Text = null;
        }
    }
}</span>

终于xml文档效果如图：

watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvbGlzZW55YW5n/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/SouthEast" alt="">

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FirstObject XML Editor是一个颇具特色的XML编辑器。该编辑器对中文的支持良好。能够快速载入XML文档，并生成可自己定义的树视图以显示 XML 文档的数据结构（很有特色。为其它 XML 编辑器所无）。能够调用 MSXML 分析引擎验证 XML 文档的正确性和有效性。

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