先添加名为ConfigUtil 的类文件
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Configuration;
using System.Xml;
namespace MakeSiteMap.Utils
{
/// <summary>
/// 对配置文件[App.config]进行操作
/// </summary>
public class ConfigUtil
{
#region Methods
/// <summary>
/// 通过 key 读取配置文件的值
/// </summary>
/// <param name="key"><add key="" value ="" /></param>
/// <returns></returns>
public static string Read(string key)
{
return ConfigurationManager.AppSettings[key];
}
/// <summary>
/// 保存修改后的配置文件
/// </summary>
/// <param name="key">键</param>
/// <param name="value">值</param>
public static void SaveConfig(string key, string value)
{
Configuration cfg = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
cfg.AppSettings.Settings[key].Value = value;
cfg.Save(ConfigurationSaveMode.Modified);
}
/// <summary>
/// 保存修改后的配置文件[XML方式]
/// </summary>
/// <param name="key">键</param>
/// <param name="value">值</param>
public static void Save(string key, string value)
{
XmlDocument doc = new XmlDocument();
string config = AppDomain.CurrentDomain.SetupInformation.ConfigurationFile;
doc.Load(config);
XmlNodeList nodes = doc.GetElementsByTagName("add");
for (int i = 0; i < nodes.Count; i++)
{
XmlAttribute att = nodes[i].Attributes["key"];
if (att.Value == key)
{
att = nodes[i].Attributes["value"];
att.Value = value;
break;
}
}
doc.Save(config);
}
#endregion
}
}
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然后再配置文件中设定初始值在</appSettings>之上
<add key="CurrentNum" value="77818" />
</appSettings>
然后在程序中读取CurrentNum的值value
string file = ConfigUtil.Read("CurrentNum");
再在程序一次执行完成后修改配置文件中CurrentNum
file = ds.Tables[0].Rows[ds.Tables[0].Rows.Count - 1]["商家编码"].ToString(); //修改
ConfigUtil.SaveConfig("CurrentNum", file); //保存修改
