如何在C#中通过Microsoft Web服务扩展访问控制面板Web凭据

首先明确：.NET官方库中不存在WebCredentials静态类，没法像Environment.Example那样直接通过静态属性读取Web凭据。要访问Windows凭据管理器里的Web凭据，得用以下两种方式：

方案1：用第三方NuGet库简化操作 #

推荐使用CredentialManagement包，它封装了Windows凭据管理的API，不用自己写P/Invoke代码：

1. 在Visual Studio的NuGet包管理器中安装：Install-Package CredentialManagement
2. 示例代码：

using CredentialManagement;

// 加载所有Web类型凭据
var credentialSet = new CredentialSet { Type = CredentialType.DomainPassword };
if (credentialSet.Load())
{
    foreach (var cred in credentialSet)
    {
        Console.WriteLine($"目标地址: {cred.TargetName}, 用户名: {cred.UserName}, 密码: {cred.Password}");
    }
}

方案2：直接调用Windows API（无第三方依赖） #

如果不想引入外部库，可以用P/Invoke直接调用Windows的CredEnumerate等API：

using System;
using System.Runtime.InteropServices;

public static class CredentialHelper
{
    [DllImport("advapi32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
    private static extern bool CredEnumerate(string filter, int flag, out int count, out IntPtr pCredentials);

    [DllImport("advapi32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
    private static extern bool CredFree(IntPtr pCredentials);

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
    private struct Credential
    {
        public int Flags;
        public int Type;
        public IntPtr TargetName;
        public IntPtr Comment;
        public System.Runtime.InteropServices.ComTypes.FILETIME LastWritten;
        public int CredentialBlobSize;
        public IntPtr CredentialBlob;
        public int Persist;
        public int AttributeCount;
        public IntPtr Attributes;
        public IntPtr TargetAlias;
        public IntPtr UserName;
    }

    public static void ListWebCredentials()
    {
        int credentialCount;
        IntPtr credentialListPtr;
        
        // 枚举所有Web凭据（"Web:"是过滤器，指定只获取Web类型的凭据）
        if (CredEnumerate("Web:", 0, out credentialCount, out credentialListPtr))
        {
            for (int i = 0; i < credentialCount; i++)
            {
                IntPtr credPtr = Marshal.ReadIntPtr(credentialListPtr, i * IntPtr.Size);
                Credential cred = Marshal.PtrToStructure<Credential>(credPtr);
                
                string target = Marshal.PtrToStringUni(cred.TargetName);
                string userName = Marshal.PtrToStringUni(cred.UserName);
                // 密码是Unicode字符串，所以要除以2计算长度
                string password = Marshal.PtrToStringUni(cred.CredentialBlob, cred.CredentialBlobSize / 2);

                Console.WriteLine($"目标: {target}, 用户名: {userName}, 密码: {password}");
            }
            // 释放API分配的内存
            CredFree(credentialListPtr);
        }
        else
        {
            int errorCode = Marshal.GetLastWin32Error();
            Console.WriteLine($"读取凭据失败，错误码: {errorCode}");
        }
    }
}

// 调用示例
CredentialHelper.ListWebCredentials();

注意事项 #

• 你已经获取了管理员权限，这是读取所有凭据的必要条件，普通权限可能无法访问部分系统凭据。
• Web凭据是一个集合，不是单个属性，所以没法通过类似WebCredentials.Passwords的方式直接获取，必须通过枚举的方式遍历所有凭据条目。

内容的提问来源于stack exchange，提问作者Fish