AppSettingsReader.GetValue(String, Type) 方法
定义
从 AppSettings 属性中获取指定键的值,并返回指定类型的对象,该对象包含来自配置文件的值。Gets the value for a specified key from the AppSettings property and returns an object of the specified type containing the value from the configuration.
public:
System::Object ^ GetValue(System::String ^ key, Type ^ type);
public object GetValue (string key, Type type);
member this.GetValue : string * Type -> obj
Public Function GetValue (key As String, type As Type) As Object
参数
- key
- String
要为其获取值的键。The key for which to get the value.
- type
- Type
要返回的对象的类型。The type of the object to return.
返回
指定键的值。The value of the specified key.
例外
<appSettings> 配置节中不存在 key。key does not exist in the <appSettings> configuration section.
- 或 --or-
key 的 <appSettings> 配置节中的值不属于 type 类型。The value in the <appSettings> configuration section for key is not of type type.
示例
下面的示例演示如何使用 GetValue 方法在配置文件的节中检索每个键的值 <appSettings> 。The following example shows how to use the GetValue method to retrieve the value for each key in the <appSettings> section of the configuration file.
static void DisplayAppSettings()
{
try
{
var reader = new AppSettingsReader();
NameValueCollection appSettings = ConfigurationManager.AppSettings;
for (int i = 0; i < appSettings.Count; i++)
{
string key = appSettings.GetKey(i);
string value = (string)reader.GetValue(key, typeof(string));
Console.WriteLine("Key : {0} Value: {1}", key, value);
}
}
catch (ConfigurationErrorsException e)
{
Console.WriteLine("[DisplayAppSettings: {0}]", e.ToString());
}
}
Private Shared Sub DisplayAppSettings()
Try
Dim reader As New AppSettingsReader()
Dim appSettings As NameValueCollection = ConfigurationManager.AppSettings
For i As Integer = 0 To appSettings.Count - 1
Dim key As String = appSettings.GetKey(i)
Dim value As String = reader.GetValue(key, GetType(String))
Console.WriteLine("Key : {0} Value: {1}", key, value)
Next i
Catch e As ConfigurationErrorsException
Console.WriteLine("[DisplayAppSettings: {0}]", e.ToString())
End Try
End Sub