若需要修改则可以打开配置文件，操作节点属性。App.config 配置文件是项目自带的xml文件, 可以使用 .net自带的类ConfigurationManager去访问，但首先需要引入System.Configuration 类库。在该配置文件中，常用的配置节点有3种：
一、数据库连接字符串节点 connectionStrings.
<connectionStrings>
<add name="HolipERP" connectionString="Server=cnhay01as02;User ID=hlpsfs;Password=8nasalt;Database=sfsData;" providerName="SQLOLEDB.1"/>
<add name="TestData" connectionString="Server=cnhay01as01;User ID=production;Password=holipserver;Database=Test_Memo_Data;" providerName="SQLOLEDB.1" />
</connectionStrings>
可用 ConfigurationManager.ConnectionStrings[name].ToString() 读取connectionString属性 ，好像找不到直接修改的方法，我是采用先删除再添加的方式修改的，其实一般也不会在程序里面动态修改这个配置字节。
二、系统参数配置 AppSettings
<appSettings>
<add key="PLC_IP" value="192.168.0.11" />
</appSettings>
这种配置是以键值对的方式存在的，可用 ConfigurationManager.AppSettings[key].ToString() 读取 value 值， 若需要修改则可以打开配置文件，操作节点属性。
Configuration appConfig = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None); //打开 vshost.exe.config
appConfig.AppSettings.Settings.Add(key, value);
appConfig.AppSettings.Settings.Remove(key);
appConfig.AppSettings.Settings[key].Value = value;
三、自定义配置 configSections
常用的有3种类型:
-
System.Configuration.SingleTagSectionHandler （属性值的方式） -
System.Configuration.DictionarySectionHandler （键值对的方式） -
System.Configuration. NameValueSectionHandler （键值对的方式）
可以加上分组标签，另外有点很重要，configSections配置节必须放在开头即configuration的第一个子元素，具体配置格式如下，
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<sectionGroup name="PLCData">
<section name="serialNum" type="System.Configuration.SingleTagSectionHandler"/>
<section name="enableAssemble" type="System.Configuration.SingleTagSectionHandler"/>
</sectionGroup>
<section name="example1" type="System.Configuration.NameValueSectionHandler "/>
</configSections>
<PLCData>
<serialNum DB="2" StartAddr="0" ByteLength="18" />
<enableAssemble DB="2" StartAddr="18" ByteLength="2" />
</PLCData>
<example1>
<add key="Hello" value="World" />
<add key="Good" value="Morning" />
</example1>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
</startup>
<connectionStrings>
<add name="HolipERP" connectionString="Server=cnhay01as02;User ID=hlpsfs;Password=8nasalt;Database=sfsData;" providerName="SQLOLEDB.1"/>
<add name="TestData" connectionString="Server=cnhay01as01;User ID=production;Password=holipserver;Database=Test_Memo_Data;" providerName="SQLOLEDB.1" />
</connectionStrings>
<appSettings>
<add key="PLC_IP" value="192.168.0.11" />
</appSettings>
</configuration>
可通过 IDictionary IDic = (IDictionary)ConfigurationManager.GetSection(setionGroupName+"/"+setionName) 读取配置，以键值对的方式保存。若需要修改，可采用xPath方式直接访问。下面这个AppConfigManagement静态类，当中的修改方法都是同时更新保存两个配置文件的，原因注释里有写到。
/// <summary>
/// winform会自动生成有2个配置文件 vshost.exe.config 和 exe.config， 修改操作必须同时修改2个文件并同时保存， 如果只修改vshost.exe.config，程序重启会重新读取exe.config将其覆盖
/// </summary>
public static class AppConfigManagement
{
private static Configuration appConfig = null; // vshost.exe.config
private static Configuration appConfig_original = null; // exe.config
private static XmlDocument doc = null; //加载 vshost.exe.config
static AppConfigManagement()
{
appConfig = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None); //打开 vshost.exe.config
appConfig_original = ConfigurationManager.OpenExeConfiguration(Assembly.GetEntryAssembly().Location); //打开 exe.config
doc = new XmlDocument(); //加载 vshost.exe.config
doc.Load(appConfig.FilePath);
}
//读取连接字符串
public static string GetConnectionStringSet(string name)
{
try
{
return ConfigurationManager.ConnectionStrings[name].ToString();
}catch(Exception err){
throw new Exception("GetConnectionStringSet:" + err.Message);
}
}
//修改连接字符串
public static void SetConnectionStringSet(string name,string value)
{
try
{
appConfig.ConnectionStrings.ConnectionStrings.Remove(name); //没有直接修改的方法，只能先删除，再创建 vshost.exe.config
appConfig_original.ConnectionStrings.ConnectionStrings.Remove(name); // .exe.config
appConfig.ConnectionStrings.ConnectionStrings.Add(new ConnectionStringSettings(name, value)); //添加vshost.exe.config
appConfig_original.ConnectionStrings.ConnectionStrings.Add(new ConnectionStringSettings(name, value)); //添加exe.config
appConfig.Save(); //保存vshost.exe.config
appConfig_original.Save(); //保存exe.config
ConfigurationManager.RefreshSection("connectionStrings"); //刷新内存中的配置值
if (!(GetConnectionStringSet(name) == value))
{ //读取比较确认修改成功
throw new Exception("Failed to SetConnectionStringSet");
}
}
catch (Exception err)
{
throw new Exception("SetConnectionStringSet:" + err.Message);
}
}
//读取程序配置
public static string GetAppSeting(string name)
{
try
{
return ConfigurationManager.AppSettings[name].ToString();
}
catch (Exception err)
{
throw new Exception("GetAppSeting:" + err.Message);
}
}
//添加程序配置
public static void AddAppSeting(string key,string value)
{
try
{
appConfig.AppSettings.Settings.Add(key, value);
appConfig_original.AppSettings.Settings.Add(key, value);
appConfig.Save(); //保存
appConfig_original.Save(); //保存
ConfigurationManager.RefreshSection("appSettings");
if (!(GetAppSeting(key) == value))
{ //读取比较确认添加成功
throw new Exception("Failed to AddAppSeting");
}
}
catch (Exception err)
{
throw new Exception("AddAppSeting:" + err.Message);
}
}
//删除程序配置
public static void DeleteAppSeting(string key)
{
try
{
appConfig.AppSettings.Settings.Remove(key);
appConfig_original.AppSettings.Settings.Remove(key);
appConfig.Save(); //保存
appConfig_original.Save(); //保存
ConfigurationManager.RefreshSection("appSettings");
}
catch (Exception err)
{
throw new Exception("DeleteAppSeting:" + err.Message);
}
}
//修改程序配置
public static void UpdateAppSeting(string key,string value)
{
try
{
appConfig.AppSettings.Settings[key].Value = value;
appConfig_original.AppSettings.Settings[key].Value = value;
appConfig.Save(); //保存
appConfig_original.Save(); //保存
ConfigurationManager.RefreshSection("appSettings");
if (!(GetAppSeting(key) == value))
{ //读取比较确认添加成功
throw new Exception("Failed to UpdateAppSeting");
}
}
catch (Exception err)
{
throw new Exception("UpdateAppSeting:" + err.Message);
}
}
//读取自定义配置节
//读取System.Configuration.SingleTagSectionHandler类型,System.Configuration.NameValueSectionHandler类型和System.Configuration.DictionarySectionHandler类型自定义配置节
public static Dictionary<string, string> GetCustomizedSection(string setionName)
{
try
{
IDictionary IDic = (IDictionary)ConfigurationManager.GetSection(setionName);
Dictionary<string,string> Dic_Copy = new Dictionary<string,string>();
foreach(object key in IDic.Keys){
Dic_Copy.Add(key.ToString(),IDic[key].ToString());
}
return Dic_Copy;
}
catch (Exception err)
{
throw new Exception("GetCustomizedSection:" + err.Message);
}
}
//读取分组的System.Configuration.SingleTagSectionHandler类型,System.Configuration.NameValueSectionHandler类型和System.Configuration.DictionarySectionHandler类型自定义配置节
public static Dictionary<string, string> GetCustomizedSection(string setionGroupName,string setionName)
{
try
{
IDictionary IDic = (IDictionary)ConfigurationManager.GetSection(setionGroupName+"/"+setionName);
Dictionary<string, string> Dic_Copy = new Dictionary<string, string>();
foreach (object key in IDic.Keys)
{
Dic_Copy.Add(key.ToString(), IDic[key].ToString());
}
return Dic_Copy;
}
catch (Exception err)
{
throw new Exception("GetCustomizedSection:" + err.Message);
}
}
//修改System.Configuration.SingleTagSectionHandler类型自定义配置节
public static void SetCustomizedSectionProperty(string setionGroup,string setionName, string propertyName, string value)
{
try
{
string xpath = "";
if (string.IsNullOrEmpty(setionGroup)) //是否有组
{
xpath = setionName;
}
else
{
xpath = setionGroup + "/" + setionName;
}
XmlNode node = doc.SelectSingleNode(@"/configuration/"+xpath); //使用xPath的方式直接访问
node.Attributes[propertyName].Value = value; //设置属性值
doc.Save(appConfig.FilePath); //保存至 vshost.exe.config
doc.Save(appConfig_original.FilePath); //保存至 exe.config
ConfigurationManager.RefreshSection(xpath); //刷新内存中的配置值
}
catch (Exception err)
{
throw new Exception("SetSingleTagSectionValue:" + err.Message);
}
}
} 