C#修改App.config以后,怎么再次启动

C#修改App.config以后,如何再次启动啊
我的App.config有一个连接数据库的地方,我想通过textbox输入以后,修改App.config的值,然后立即连接数据库。请问怎么做啊
代码如下:
<?xml version="1.0"?>
<configuration>
  <appSettings>
    <add key="ConStringEncrypt" value="false"/>
    <!--<add key="ConnectionString" value="server=192.168.0.123;database=jijiaOAICE;uid=sa;pwd=sa;pooling=false " />-->
    <add key="ConnectionString" value="server=192.168.0.xxx;database=OAICE;uid=sa;pwd=sa"/>
    <add key="AppName" value="OA"/>
  </appSettings>
  <system.serviceModel>
    <bindings>
      <basicHttpBinding>
        <binding name="AuthorityServiceSoap" closeTimeout="00:01:00" openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00" allowCookies="false" bypassProxyOnLocal="false" hostNameComparisonMode="StrongWildcard" maxBufferSize="65536" maxBufferPoolSize="524288" maxReceivedMessageSize="65536" messageEncoding="Text" textEncoding="utf-8" transferMode="Buffered" useDefaultWebProxy="true">
          <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384" maxBytesPerRead="4096" maxNameTableCharCount="16384"/>
          <security mode="None">
            <transport clientCredentialType="None" proxyCredentialType="None" realm=""/>
            <message clientCredentialType="UserName" algorithmSuite="Default"/>
          </security>
        </binding>
      </basicHttpBinding>
    </bindings>

  </system.serviceModel>
  <startup>
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/>
  </startup>
</configuration>

------解决方案--------------------
ConfigurationManager.RefreshSection("yoursection/subsection");


参考:
.net dynamically refresh app.config
http://*.com/questions/272097/net-dynamically-refresh-app-config
------解决方案--------------------
点击按钮保存 把当前值写入到app.config你会吧..

然后重新开启一个当前的exe并且把这个exe关闭就行了..

所谓的再次启动不就是关闭在运行吗...
------解决方案--------------------
Application.Exit();
Application.Restart();