public FileExtensionContentTypeProvider(
	IDictionary<string, string> mapping
)Public Sub New ( 
	mapping As IDictionary(Of String, String)
)new : 
        mapping : IDictionary<string, string> -> FileExtensionContentTypeProvider[缺少 "M:TouchSocket.Http.FileExtensionContentTypeProvider.#ctor(System.Collections.Generic.IDictionary{System.String,System.String})" 的 <param name="mapping"/> 文档]