HttpWebRequest.Credentials 属性
定义
重要
一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。 对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。
获取或设置请求的身份验证信息。
public:
virtual property System::Net::ICredentials ^ Credentials { System::Net::ICredentials ^ get(); void set(System::Net::ICredentials ^ value); };public override System.Net.ICredentials Credentials { get; set; }public override System.Net.ICredentials? Credentials { get; set; }member this.Credentials : System.Net.ICredentials with get, setPublic Overrides Property Credentials As ICredentials属性值
包含与请求关联的身份验证凭据的 ICredentials。 默认值为 null。
示例
下面的代码示例设置请求的凭据。
using System;
using System.Net;
using System.Text;
using System.IO;
public class Test
{
// Specify the URL to receive the request.
public static void Main (string[] args)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(args[0]);
// Set some reasonable limits on resources used by this request
request.MaximumAutomaticRedirections = 4;
request.MaximumResponseHeadersLength = 4;
// Set credentials to use for this request.
request.Credentials = CredentialCache.DefaultCredentials;
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Console.WriteLine("Content length is {0}", response.ContentLength);
Console.WriteLine("Content type is {0}", response.ContentType);
// Get the stream associated with the response.
Stream receiveStream = response.GetResponseStream();
// Pipes the stream to a higher level stream reader with the required encoding format.
StreamReader readStream = new StreamReader(receiveStream, Encoding.UTF8);
Console.WriteLine("Response stream received.");
Console.WriteLine(readStream.ReadToEnd());
response.Close();
readStream.Close();
}
}
/*
The output from this example will vary depending on the value passed into Main
but will be similar to the following:
Content length is 1542
Content type is text/html; charset=utf-8
Response stream received.
<html>
...
</html>
*/
Imports System.Net
Imports System.Text
Imports System.IO
Public Class Test
' Specify the URL to receive the request.
Public Shared Sub Main(ByVal args() As String)
Dim request As HttpWebRequest = CType(WebRequest.Create(args(0)), HttpWebRequest)
' Set some reasonable limits on resources used by this request
request.MaximumAutomaticRedirections = 4
request.MaximumResponseHeadersLength = 4
' Set credentials to use for this request.
request.Credentials = CredentialCache.DefaultCredentials
Dim response As HttpWebResponse = CType(request.GetResponse(), HttpWebResponse)
Console.WriteLine("Content length is {0}", response.ContentLength)
Console.WriteLine("Content type is {0}", response.ContentType)
' Get the stream associated with the response.
Dim receiveStream As Stream = response.GetResponseStream()
' Pipes the stream to a higher level stream reader with the required encoding format.
Dim readStream As New StreamReader(receiveStream, Encoding.UTF8)
Console.WriteLine("Response stream received.")
Console.WriteLine(readStream.ReadToEnd())
response.Close()
readStream.Close()
End Sub
End Class
'
'The output from this example will vary depending on the value passed into Main
'but will be similar to the following:
'
'Content length is 1542
'Content type is text/html; charset=utf-8
'Response stream received.
'...
'
'
注解
谨慎
WebRequest、HttpWebRequest、ServicePoint和 WebClient 已过时，不应将其用于新开发。 请改用 HttpClient。
Credentials 属性包含身份验证信息，用于标识请求的创建者。 Credentials 属性可以是 NetworkCredential，在这种情况下，NetworkCredential 对象中包含的用户、密码和域信息用于对请求进行身份验证，也可以是 CredentialCache，在这种情况下，请求的统一资源标识符（URI）用于确定用于对请求进行身份验证的用户、密码和域信息。
在大多数客户端方案中，应使用 DefaultCredentials 属性，该属性包含当前登录用户的凭据。 为此，请将 UseDefaultCredentials 属性设置为 true，而不是设置此属性。
如果在中间层应用程序中（如 ASP.NET 应用程序）中使用 HttpWebRequest 类，则 DefaultCredentials 属性中的凭据属于运行 ASP 页的帐户（服务器端凭据）。 通常，将此属性设置为代表发出请求的客户端的凭据。
注意
NTLM 身份验证方案不能用于模拟其他用户。 必须专门配置 Kerberos 以支持模拟。
若要将 HttpWebRequest 限制为一个或多个身份验证方法，请使用 CredentialCache 类并将凭据绑定到一个或多个身份验证方案
支持的身份验证方案包括 Digest、Negotiate、Kerberos、NTLM 和 Basic。
出于安全原因，在自动关注重定向时，请将要包含在重定向中的凭据存储在 CredentialCache 中，并将其分配给此属性。 如果此属性包含除 CredentialCache以外的任何内容，则此属性将自动设置为在重定向时 null。 在这些情况下，将此属性值自动设置为 null 可防止将凭据发送到任何意外的目标。
