Aras学习笔记 (12) C#代码读取域用户列表（转，翻译）

Get List of Active Directory Users in C# - 作者原文标题

Introduction 

This tip describes how to list Active Directory users.  介绍如何提取AD域中的用户列表

Using the Code 

The below code demonstrates how can we fetch Active Directory (AD) using Directory Service. For this, I'm using object array (Users) and here is the structure:

首先创建实体类，用户保存用户信息。

public class Users
{
    public string Email { get; set; }
    public string UserName { get; set; }
    public string DisplayName { get; set; }
    public bool isMapped { get; set; }
}

The code below shows how to fetch user information from Active Directory.

以下代码为如何AD域中的用户信息。

public List<Users> GetADUsers()
{
    try
    {
        List<Users> lstADUsers = new List<Users>();　　//定义返回列表
        string DomainPath = "LDAP://DC=xxxx,DC=com"　//改为自己公司的LDAP访问地址
        DirectoryEntry searchRoot = new DirectoryEntry(DomainPath); 
        DirectorySearcher search = new DirectorySearcher(searchRoot);
        search.Filter = "(&(objectClass=user)(objectCategory=person))";
        search.PropertiesToLoad.Add("samaccountname");　　//提取samaccountname,mail,usergroup和displayname四个字段
        search.PropertiesToLoad.Add("mail");
        search.PropertiesToLoad.Add("usergroup");
        search.PropertiesToLoad.Add("displayname");//first name
        SearchResult result;
        SearchResultCollection resultCol = search.FindAll();　　//执行查询
        if (resultCol != null)
        {
            for (int counter = 0; counter < resultCol.Count; counter++)　　//循环读取
            {
                string UserNameEmailString = string.Empty;
                result = resultCol[counter];
                if (result.Properties.Contains("samaccountname") && 
                         result.Properties.Contains("mail") && 
                    result.Properties.Contains("displayname"))
                {
                    Users objSurveyUsers = new Users();
                    objSurveyUsers.Email = (String)result.Properties["mail"][0] + 
                      "^" + (String)result.Properties["displayname"][0];
                    objSurveyUsers.UserName = (String)result.Properties["samaccountname"][0];
                    objSurveyUsers.DisplayName = (String)result.Properties["displayname"][0];
                    lstADUsers.Add(objSurveyUsers);
                }
            }
        }
        return lstADUsers;　　//返回
    }
    catch (Exception ex)
    {
 
}

Let's see what is happening here... 实现原理介绍

The DirectoryEntry class encapsulates an object in Active Directory Domain Services, DirectoryEntry(DomainPath) initializes a new instance of the class that binds this instance to the node in Active Directory Domain Services located at the specified path, i.e., DomainPath.

In DirectorySearcher, create a DirectorySearcher object which searches for all users in a domain. search.Filter = "(&(objectClass=user)(objectCategory=person))" filters the search.

The search filter syntax looks a bit complicated, but basically it filters the search results to only include users - "objectCategory=person" and "objectClass=user" - and excludes disabled user accounts by performing a bitwise AND of the userAccountControl flags and the "account disabled" flag.

Note: SAMAccountName is unique and also indexed. sAMAccountName must be unique among all security principal objects within the domain.

search.FindAll(); retrieves all the elements that match the conditions defined.

Let's see how we get the current login user.

//获取当前登录域用户

public string GetCurrentUser()
{
    try
    {
        string userName = HttpContext.Current.User.Identity.Name.Split('\\')[1].ToString();
        string displayName = GetAllADUsers().Where(x => 
          x.UserName == userName).Select(x => x.DisplayName).First();
        return displayName;
    }
    catch (Exception ex)
    { //Exception logic here 
    }
}

Let's see what this code snippet does:

• HttpContext.Current.User.Identity returns the Windows identity object including AuthenticationType ("ntml", "kerberos" etc..), IsAuthenticated, Name ("Domain/username").
• HttpContext.Current.User.Identity.Name returns "Domain\\username" .

Hope this helps you understand how directory service works with AD. //感谢原作者Naufel Basheer大神