ConfigurationManager.GetSection(String) 方法

public:
 static System::Object ^ GetSection(System::String ^ sectionName);

public static object GetSection (string sectionName);

static member GetSection : string -> obj

Public Shared Function GetSection (sectionName As String) As Object

指定的 ConfigurationSection 对象，如果该节不存在，则为 null。

下面的示例显示如何使用 GetSection 方法。 该示例是为 类提供的更大示例的一 ConfigurationManager 部分。

// Create the AppSettings section.
// The function uses the GetSection(string)method 
// to access the configuration section. 
// It also adds a new element to the section collection.
public static void CreateAppSettings()
{
  // Get the application configuration file.
  System.Configuration.Configuration config =
    ConfigurationManager.OpenExeConfiguration(
          ConfigurationUserLevel.None);

  string sectionName = "appSettings";

  // Add an entry to appSettings.
  int appStgCnt =
      ConfigurationManager.AppSettings.Count;
  string newKey = "NewKey" + appStgCnt.ToString();

  string newValue = DateTime.Now.ToLongDateString() + 
    " " + DateTime.Now.ToLongTimeString();

  config.AppSettings.Settings.Add(newKey, newValue);

  // Save the configuration file.
  config.Save(ConfigurationSaveMode.Modified);
  
  // Force a reload of the changed section. This 
  // makes the new values available for reading.
  ConfigurationManager.RefreshSection(sectionName);

  // Get the AppSettings section.
  AppSettingsSection appSettingSection =
    (AppSettingsSection)config.GetSection(sectionName);

  Console.WriteLine();
  Console.WriteLine("Using GetSection(string).");
  Console.WriteLine("AppSettings section:");
  Console.WriteLine(
    appSettingSection.SectionInformation.GetRawXml());
}

' Create the AppSettings section.
' The function uses the GetSection(string)method 
' to access the configuration section. 
' It also adds a new element to the section collection.
Public Shared Sub CreateAppSettings()
    ' Get the application configuration file.
    Dim config As System.Configuration.Configuration = _
    ConfigurationManager.OpenExeConfiguration( _
        ConfigurationUserLevel.None)

    Dim sectionName As String = "appSettings"

    ' Add an entry to appSettings.
    Dim appStgCnt As Integer = _
        ConfigurationManager.AppSettings.Count
    Dim newKey As String = _
        "NewKey" + appStgCnt.ToString()

    Dim newValue As String = _
        DateTime.Now.ToLongDateString() + " " + _
        DateTime.Now.ToLongTimeString()

    config.AppSettings.Settings.Add(newKey, _
                                    newValue)

    ' Save the configuration file.
    config.Save(ConfigurationSaveMode.Modified)

    ' Force a reload of the changed section. This 
    ' makes the new values available for reading.
    ConfigurationManager.RefreshSection(sectionName)

    ' Get the AppSettings section.
    Dim appSettingSection As AppSettingsSection = _
        DirectCast(config.GetSection(sectionName),  _
        AppSettingsSection)

    Console.WriteLine()
    Console.WriteLine( _
        "Using GetSection(string).")
    Console.WriteLine( _
        "AppSettings section:")
    Console.WriteLine( _
        appSettingSection.SectionInformation.GetRawXml())
End Sub

对于客户端应用程序，此方法检索通过合并应用程序配置文件、本地用户配置文件和漫游配置文件获取的配置文件。

方法 GetSection 访问无法更改的运行时配置信息。 若要更改配置，请在 GetSection 使用以下方法之一获取的配置文件上使用 方法：

• OpenExeConfiguration

• OpenMachineConfiguration

• OpenMappedExeConfiguration

必须将返回值强制转换为预期的配置类型。 为了避免可能的强制转换异常，应使用条件转换操作，例如 as C# 中的 运算符或 Visual Basic 中的 TryCast 函数。

• ConfigurationSection