C#中对Web.config配置文件的操作（增删改读） [转]

C#中对Web.config配置文件的操作（增删改读）

using System;
using System.Configuration;
using System.Reflection;
using System.Web;
using System.Xml;
public enum ConfigFileType
{
WebConfig,
AppConfig
}

namespace ConfigRW
{
/// <summary>
/// Summary description for ReadWriteConfig.
/// </summary>
public class ReadWriteConfig
{
public string docName = String.Empty;
private XmlNode node=null;
private int _configType;
public string message;
public int ConfigType
{
get{ return _configType; }
set{ _configType=value; }
}

#region GetValue
public string GetValue( string key )
{ //读取
try
{
XmlDocument cfgDoc = new XmlDocument();
loadConfigDoc(cfgDoc);
// retrieve the appSettings node
node = cfgDoc.SelectSingleNode("//appSettings");
if( node == null )
{
throw new InvalidOperationException( "appSettings section not found");
}
// XPath select setting "add" element that contains this key to remove
XmlElement addElem= (XmlElement)node.SelectSingleNode("//add[@key='" +key +"']") ;
if(addElem == null)
{
message = "此key不存在！";
return message;
}
message = System.Configuration.ConfigurationSettings.AppSettings[key];
return message;
}
catch
{
message = "操作异常，获取value值失败！";
return message;
}
}
#endregion

#region SetValue
public string SetValue(string key, string value)
{ //增加
XmlDocument cfgDoc = new XmlDocument();
loadConfigDoc(cfgDoc);
// retrieve the appSettings node
node = cfgDoc.SelectSingleNode("//appSettings");
if( node == null )
{
throw new InvalidOperationException( "appSettings section not found");
}
try
{
// XPath select setting "add" element that contains this key
XmlElement addElem= (XmlElement)node.SelectSingleNode("//add[@key='" +key +"']") ;
if(addElem!=null)
{
message = "此key已经存在！";
return message;
}
// not found, so we need to add the element, key and value
else
{
XmlElement entry = cfgDoc.CreateElement("add");
entry.SetAttribute("key",key);
entry.SetAttribute("value",value);
node.AppendChild(entry);
}
//save it
saveConfigDoc(cfgDoc,docName);
message = "添加成功！";
return message;
}
catch
{
message = "操作异常，添加失败！";
return message;
}
}

#endregion

#region saveConfigDoc
private void saveConfigDoc(XmlDocument cfgDoc,string cfgDocPath)
{
try
{
XmlTextWriter writer = new XmlTextWriter( cfgDocPath , null );
writer.Formatting = Formatting.Indented;
cfgDoc.WriteTo( writer );
writer.Flush();
writer.Close();
return;
}
catch
{
throw;
}
}

#endregion

#region removeElement
public string removeElement (string elementKey)
{ // 删除
try
{
XmlDocument cfgDoc = new XmlDocument();
loadConfigDoc(cfgDoc);
// retrieve the appSettings node
node = cfgDoc.SelectSingleNode("//appSettings");
if( node == null )
{

throw new InvalidOperationException( "appSettings section not found");
}

XmlElement addElem= (XmlElement)node.SelectSingleNode("//add[@key='" +elementKey +"']") ;
if(addElem == null)
{
message = "此key不存在！";
return message;
}
// XPath select setting "add" element that contains this key to remove
node.RemoveChild( node.SelectSingleNode("//add[@key='" +elementKey +"']") );
saveConfigDoc(cfgDoc,docName);
message = "删除成功！";
return message;
}
catch
{
message = "操作异常，删除失败！";
return message;
}
}
#endregion

#region modifyElement
public string modifyElement (string elementKey, string elementValue)
{ //修改
try
{
XmlDocument cfgDoc = new XmlDocument();
loadConfigDoc(cfgDoc);
// retrieve the appSettings node
node = cfgDoc.SelectSingleNode("//appSettings");
if( node == null )
{
throw new InvalidOperationException( "appSettings section not found");
}
// XPath select setting "add" element that contains this key to remove
XmlElement addElem= (XmlElement)node.SelectSingleNode("//add[@key='" +elementKey +"']") ;
if(addElem == null)
{
message = "此key不存在！";
return message;
}

addElem.SetAttribute("value",elementValue);
//save it
saveConfigDoc(cfgDoc,docName);
message = "修改成功！";
return message;
}
catch
{
message = "操作异常，修改失败！";
return message;
}
}
#endregion

#region loadConfigDoc
private XmlDocument loadConfigDoc( XmlDocument cfgDoc )
{
// load the config file
if( Convert.ToInt32(ConfigType)==Convert.ToInt32(ConfigFileType.AppConfig))
{
docName= ((Assembly.GetEntryAssembly()).GetName()).Name;
docName += ".exe.config";
}
else
{
docName=HttpContext.Current.Server.MapPath("web.config");
}
cfgDoc.Load( docName );
return cfgDoc;
}
#endregion
}
}

 

测试页面

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;

namespace ConfigRW
{
/// <summary>
/// Summary description for WebForm1.
/// </summary>
public class WebForm1 : System.Web.UI.Page
{
protected System.Web.UI.WebControls.Button Button1;
protected System.Web.UI.WebControls.Label Label1;
protected System.Web.UI.WebControls.TextBox TextBox1;
protected System.Web.UI.WebControls.Label Label2;
protected System.Web.UI.WebControls.TextBox TextBox2;
protected System.Web.UI.WebControls.Button Button3;
protected System.Web.UI.WebControls.Button Button4;
protected System.Web.UI.WebControls.Button Button2;

private void Page_Load(object sender, System.EventArgs e)
{

}

#region Web Form Designer generated code
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: This call is required by the ASP.NET Web Form Designer.
//
InitializeComponent();
base.OnInit(e);
}

/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.Button1.Click += new System.EventHandler(this.Button1_Click);
this.Button2.Click += new System.EventHandler(this.Button2_Click);
this.Button3.Click += new System.EventHandler(this.Button3_Click);
this.Button4.Click += new System.EventHandler(this.Button4_Click);
this.Load += new System.EventHandler(this.Page_Load);

}
#endregion

private void Button2_Click(object sender, System.EventArgs e)
{
//新增
ReadWriteConfig config = new ReadWriteConfig();
config.ConfigType = (int)ConfigFileType.WebConfig;
Response.Write(config.SetValue(this.TextBox1.Text,this.TextBox2.Text));
}

private void Button1_Click(object sender, System.EventArgs e)
{
//删除
ReadWriteConfig config = new ReadWriteConfig();
config.ConfigType = (int)ConfigFileType.WebConfig;
Response.Write(config.removeElement(this.TextBox1.Text));
}

private void Button3_Click(object sender, System.EventArgs e)
{
//修改
ReadWriteConfig config = new ReadWriteConfig();
config.ConfigType = (int)ConfigFileType.WebConfig;
Response.Write(config.modifyElement(this.TextBox1.Text,this.TextBox2.Text));
}

private void Button4_Click(object sender, System.EventArgs e)
{
//读取
ReadWriteConfig config = new ReadWriteConfig();
config.ConfigType = (int)ConfigFileType.WebConfig;
this.TextBox2.Text = config.GetValue(this.TextBox1.Text);
}
}
}