C# ORM學習筆記：使用特性+反射實現簡單ORM
1、原理與環境
在生成數據表的實體類時，利用自定義特性，給它打上表及字段的特性，而後使用反射原理，將自定義特性拼接成增、刪、改、查對應的SQL，便可完成一個簡單的ORM。數據庫
本示例的執行環境：緩存
1）數據庫：SQL Server。（可根據本身的須要，創建不一樣的數據庫工廠。）架構
2）數據表：需使用自增類型(identity)做爲數據表的主鍵。主鍵名字能夠隨便起，如ID。ide
3）實體類：實體類需提供無參構造函數。函數
2、演示數據表
Person表，包含主鍵（ID）、姓名（Name）、年齡（Age）、性別（Gender）。測試
CREATE TABLE [dbo].[Person]( [ID] [BIGINT] IDENTITY(1,1) NOT NULL, [Name] [NVARCHAR](50) NULL, [Age] [INT] NULL, [Gender] [NVARCHAR](10) NULL, CONSTRAINT [PK_Person] PRIMARY KEY CLUSTERED ( [ID] ASC)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]) ON [PRIMARY]
2、自定義特性
定義兩個自定義特性：ui
2.一、DataTableAttribute
此爲數據表特性，包含表名（TableName）、主鍵（Key）。this
[Serializable] public class DataTableAttribute : Attribute
{ ///
/// 數據表 ///
public string TableName { get; } ///
/// 主鍵 ///
public string Key { get; } ///
/// 構造函數 ///
///
///
public DataTableAttribute(string tableName, string key)
{
TableName = tableName;
Key = key;
}
}
2.二、DataFieldAttribute
此爲字段特性，包含字段名（FieldName）、字段類型（FieldType）、長度（Length）、是否自增（IsIdentity）。spa
[Serializable] public class DataFieldAttribute : Attribute
{ public string FieldName { get; set; } public string FieldType { get; set; } public int Length { get; set; } public bool IsIdentity { get; set; } ///
/// 構造函數 ///
/// 字段名
/// 字段類型
/// 長度
/// 是否自增加
public DataFieldAttribute(string fieldName, string fieldType, int length, bool isIdentity)
{
FieldName = fieldName;
FieldType = fieldType;
Length = length;
IsIdentity = isIdentity;
} ///
/// 構造函數 ///
///
///
///
public DataFieldAttribute(string fieldName, string fieldType, int length) : this(fieldName, fieldType, length, false)
{ } ///
/// 構造函數 ///
///
///
public DataFieldAttribute(string fieldName, string fieldType) : this(fieldName, fieldType, 0, false)
{ } ///
/// 構造函數 ///
///
///
public DataFieldAttribute(string fieldName, bool isIdentity) : this(fieldName, "", 0, isIdentity)
{ } ///
/// 構造函數 ///
///
public DataFieldAttribute(string fieldName) : this(fieldName, false)
{ }
}
3、生成實體類
3.一、實體類樣式
依照前面的規劃，Person表須要生成下面這個樣子：debug
using System;using System.Collections.Generic;using System.Text;using LinkTo.ORM.CustomAttribute;namespace LinkTo.ORM.Model
{
[DataTable("Person","ID")]
[Serializable] public class Person
{ public Person() { }
[DataField("ID","bigint",19,true)] public long? ID {get; set;}
[DataField("Name","nvarchar",50,false)] public string Name {get; set;}
[DataField("Age","int",10,false)] public int? Age {get; set;}
[DataField("Gender","nvarchar",10,false)] public string Gender {get; set;}
}
}
3.二、使用T4模板生成實體類
3.2.一、T4Code文件夾的文本模板
<#@ assembly name="System.Core" #>
<#@ assembly name="System.Data" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="System.Text" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ import namespace="System.Data"#>
<#@ import namespace="System.Data.SqlClient"#>
<#+ #region T4Code ///
/// 數據庫架構接口 ///
public interface IDBSchema : IDisposable
{
List<string> GetTableList();
DataTable GetTableMetadata(string tableName);
} ///
/// 數據庫架構工廠 ///
public class DBSchemaFactory
{ static readonly string DatabaseType = "SqlServer"; public static IDBSchema GetDBSchema()
{
IDBSchema dbSchema; switch (DatabaseType)
{ case "SqlServer":
{
dbSchema =new SqlServerSchema(); break;
} default:
{ throw new ArgumentException("The input argument of DatabaseType is invalid.");
}
} return dbSchema;
}
} ///
/// SqlServer ///
public class SqlServerSchema : IDBSchema
{ public string ConnectionString = "Server=.;Database=Test;Uid=sa;Pwd=********;"; public SqlConnection conn; public SqlServerSchema()
{
conn = new SqlConnection(ConnectionString);
conn.Open();
} public List<string> GetTableList()
{
List<string> list = new List<string>(); string commandText = "SELECT NAME TABLE_NAME FROM SYSOBJECTS WHERE XTYPE='U' ORDER BY NAME"; using(SqlCommand cmd = new SqlCommand(commandText, conn))
{ using (SqlDataReader dr = cmd.ExecuteReader(CommandBehavior.CloseConnection))
{ while (dr.Read())
{
list.Add(dr["TABLE_NAME"].ToString());
}
}
} return list;
}
public DataTable GetTableMetadata(string tableName)
{ string commandText=string.Format
( "SELECT A.NAME TABLE_NAME,B.NAME FIELD_NAME,C.NAME DATATYPE,ISNULL(B.PREC,0) LENGTH, "+ "CONVERT(BIT,CASE WHEN NOT F.ID IS NULL THEN 1 ELSE 0 END) ISKEY, "+ "CONVERT(BIT,CASE WHEN COLUMNPROPERTY(B.ID,B.NAME,'ISIDENTITY') = 1 THEN 1 ELSE 0 END) AS ISIDENTITY, "+ "CONVERT(BIT,B.ISNULLABLE) ISNULLABLE "+ "FROM SYSOBJECTS A INNER JOIN SYSCOLUMNS B ON A.ID=B.ID INNER JOIN SYSTYPES C ON B.XTYPE=C.XUSERTYPE "+ "LEFT JOIN SYSOBJECTS D ON B.ID=D.PARENT_OBJ AND D.XTYPE='PK' "+ "LEFT JOIN SYSINDEXES E ON B.ID=E.ID AND D.NAME=E.NAME "+ "LEFT JOIN SYSINDEXKEYS F ON B.ID=F.ID AND B.COLID=F.COLID AND E.INDID=F.INDID "+ "WHERE A.XTYPE='U' AND A.NAME='{0}' "+ "ORDER BY A.NAME,B.COLORDER", tableName
); using(SqlCommand cmd = new SqlCommand(commandText, conn))
{
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
da.Fill(ds,"Schema"); return ds.Tables[0];
}
} public void Dispose()
{ if (conn != null)
{
conn.Close();
}
}
} #endregion#>
DBSchema.ttinclude
<#@ assembly name="System.Core" #>
<#@ assembly name="System.Data" #>
<#@ assembly name="EnvDTE" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="System.Text" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ import namespace="System.Data"#>
<#@ import namespace="System.IO"#>
<#@ import namespace="Microsoft.VisualStudio.TextTemplating"#>
<#+// T4 Template Block manager for handling multiple file outputs more easily.// Copyright (c) Microsoft Corporation.All rights reserved.// This source code is made available under the terms of the Microsoft Public License (MS-PL)// Manager class records the various blocks so it can split them upclass Manager
{ public struct Block
{ public string Name; public int Start, Length;
} public Listblocks = new List(); public Block currentBlock; public Block footerBlock = new Block(); public Block headerBlock = new Block(); public ITextTemplatingEngineHost host; public ManagementStrategy strategy; public StringBuilder template; public string OutputPath { get; set; } public Manager(ITextTemplatingEngineHost host, StringBuilder template, bool commonHeader)
{ this.host = host; this.template = template;
OutputPath = string.Empty;
strategy = ManagementStrategy.Create(host);
} public void StartBlock(string name)
{
currentBlock = new Block { Name = name, Start = template.Length };
} public void StartFooter()
{
footerBlock.Start = template.Length;
} public void EndFooter()
{
footerBlock.Length = template.Length - footerBlock.Start;
} public void StartHeader()
{
headerBlock.Start = template.Length;
} public void EndHeader()
{
headerBlock.Length = template.Length - headerBlock.Start;
}
public void EndBlock()
{
currentBlock.Length = template.Length - currentBlock.Start;
blocks.Add(currentBlock);
} public void Process(bool split)
{ string header = template.ToString(headerBlock.Start, headerBlock.Length); string footer = template.ToString(footerBlock.Start, footerBlock.Length);
blocks.Reverse(); foreach(Block block in blocks) { string fileName = Path.Combine(OutputPath, block.Name); if (split) { string content = header + template.ToString(block.Start, block.Length) + footer;
strategy.CreateFile(fileName, content);
template.Remove(block.Start, block.Length);
} else {
strategy.DeleteFile(fileName);
}
}
}
}class ManagementStrategy
{ internal static ManagementStrategy Create(ITextTemplatingEngineHost host)
{ return (host is IServiceProvider) ? new VSManagementStrategy(host) : new ManagementStrategy(host);
} internal ManagementStrategy(ITextTemplatingEngineHost host) { } internal virtual void CreateFile(string fileName, string content)
{
File.WriteAllText(fileName, content);
} internal virtual void DeleteFile(string fileName)
{ if (File.Exists(fileName))
File.Delete(fileName);
}
}class VSManagementStrategy : ManagementStrategy
{ private EnvDTE.ProjectItem templateProjectItem; internal VSManagementStrategy(ITextTemplatingEngineHost host) : base(host)
{
IServiceProvider hostServiceProvider = (IServiceProvider)host; if (hostServiceProvider == null) throw new ArgumentNullException("Could not obtain hostServiceProvider");
EnvDTE.DTE dte = (EnvDTE.DTE)hostServiceProvider.GetService(typeof(EnvDTE.DTE)); if (dte == null) throw new ArgumentNullException("Could not obtain DTE from host");
templateProjectItem = dte.Solution.FindProjectItem(host.TemplateFile);
} internal override void CreateFile(string fileName, string content)
{ base.CreateFile(fileName, content);
((EventHandler)delegate { templateProjectItem.ProjectItems.AddFromFile(fileName); }).BeginInvoke(null, null, null, null);
} internal override void DeleteFile(string fileName)
{
((EventHandler)delegate { FindAndDeleteFile(fileName); }).BeginInvoke(null, null, null, null);
} private void FindAndDeleteFile(string fileName)
{ foreach(EnvDTE.ProjectItem projectItem in templateProjectItem.ProjectItems)
{ if (projectItem.get_FileNames(0) == fileName)
{
projectItem.Delete(); return;
}
}
}
}
#>
MultiDocument.ttinclude
DBSchema.ttinclude主要實現了數據庫工廠的功能。注：請將數據庫鏈接字符串改爲您本身的。
MultiDocument.ttinclude主要實現了多文檔的功能。
3.2.二、生成實體類的文本模板
<#@ template debug="true" hostspecific="true" language="C#" #>
<#@ assembly name="System.Core" #>
<#@ import namespace="System.Linq" #>
<#@ import namespace="System.Text" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ output extension=".cs" #>
<#@ include file="T4Code/DBSchema.ttinclude"#>
<#@ include file="T4Code/MultiDocument.ttinclude"#>
<# var manager = new Manager(Host, GenerationEnvironment, true) { OutputPath = Path.GetDirectoryName(Host.TemplateFile)}; #>
<# //System.Diagnostics.Debugger.Launch();//調試
var dbSchema = DBSchemaFactory.GetDBSchema();
List<string> tableList = dbSchema.GetTableList(); foreach (string tableName in tableList)
{
manager.StartBlock(tableName+".cs");
DataTable table = dbSchema.GetTableMetadata(tableName); //獲取主鍵
string strKey = string.Empty; foreach (DataRow dataRow in table.Rows)
{ if ((bool)dataRow["ISKEY"] == true)
{
strKey = dataRow["FIELD_NAME"].ToString(); break;
}
}
#>//-------------------------------------------------------------------------------// 此代碼由T4模板MultModelAuto自動生成// 生成時間 // 對此文件的更改可能會致使不正確的行爲，而且若是從新生成代碼，這些更改將會丟失。//-------------------------------------------------------------------------------using System;using System.Collections.Generic;using System.Text;using LinkTo.ORM.CustomAttribute;namespace LinkTo.ORM.Model
{
[DataTable("","")]
[Serializable] public class
{ public () { }<# foreach (DataRow dataRow in table.Rows)
{ //獲取數據類型
string dbDataType = dataRow["DATATYPE"].ToString(); string dataType = string.Empty;
switch (dbDataType)
{ case "decimal": case "numeric": case "money": case "smallmoney":
dataType = "decimal?"; break; case "char": case "nchar": case "varchar": case "nvarchar": case "text": case "ntext":
dataType = "string"; break; case "uniqueidentifier":
dataType = "Guid?"; break; case "bit":
dataType = "bool?"; break; case "real":
dataType = "Single?"; break; case "bigint":
dataType = "long?"; break; case "int":
dataType = "int?"; break; case "tinyint": case "smallint":
dataType = "short?"; break; case "float":
dataType = "float?"; break; case "date": case "datetime": case "datetime2": case "smalldatetime":
dataType = "DateTime?"; break; case "datetimeoffset ":
dataType = "DateTimeOffset?"; break; case "timeSpan ":
dataType = "TimeSpan?"; break; case "image": case "binary": case "varbinary":
dataType = "byte[]"; break; default: break;
}
#>
[DataField("<#= dataRow["FIELD_NAME"].ToString() #>","<#= dataRow["DATATYPE"].ToString() #>",<#= dataRow["LENGTH"].ToString() #>,<#= dataRow["ISIDENTITY"].ToString().ToLower() #>)] public <#= dataRow["FIELD_NAME"].ToString() #> {get; set;}<#
}
#>
}
}<#
manager.EndBlock();
}
dbSchema.Dispose();
manager.Process(true);
#>
MultiModelAuto.tt
注：因爲ORM拼接SQL時使用的是表特性及字段特性，能夠看出表特性上使用的表名、字段特性上使用的字段名，都是與數據庫一致的。有了這個保障，數據表生成實體類的時候，類名是能夠更改的，由於我只須要保證表特性與數據庫一致便可。舉個例子，我有個數據表Person_A，在生成實體類時，類名能夠生成爲Class PersonA {...}，可是表特性依然是[DataTable("Person_A","...")]。相同的原理，屬性名也是能夠更改的。
4、ORM實現
數據表的CURD，主要是經過反射來實現SQL拼接，實現以下：
using System;using System.Collections;using System.Collections.Generic;using System.Data;using System.Data.SqlClient;using System.Linq;using System.Reflection;using System.Text;using System.Threading.Tasks;using LinkTo.ORM.CustomAttribute;namespace LinkTo.ORM
{ public static class DBHelper
{ public static readonly string ConnectionString = "Server=.;Database=Test;Uid=sa;Pwd=********;"; private static readonly Hashtable _HashTableName = new Hashtable(); //表名緩存
private static readonly Hashtable _HashKey = new Hashtable(); //主鍵緩存
///
/// 數據庫鏈接 ///
///
public static SqlConnection GetConnection()
{
SqlConnection conn = new SqlConnection(ConnectionString); return conn;
} ///
/// 新增 ///
///
///
///
public static int Insert(TEntity entity) where TEntity : class
{ string strTableName = ""; //表名
string strInsertSQL = "INSERT INTO {0} ({1}) VALUES ({2})"; //SQL拼接語句 //獲取表名
strTableName = GetTableName(entity); //獲取字段列表及值列表
StringBuilder strFields = new StringBuilder();
StringBuilder strValues = new StringBuilder();
ListparaList = new List();
PropertyInfo[] infos = entity.GetType().GetProperties();
DataFieldAttribute dfAttr = null; object[] dfAttrs; int i = 0; foreach (PropertyInfo info in infos)
{
dfAttrs = info.GetCustomAttributes(typeof(DataFieldAttribute), false); if (dfAttrs.Length > 0)
{
dfAttr = dfAttrs[0] as DataFieldAttribute; if (dfAttr is DataFieldAttribute)
{ //自增字段不做處理
if (dfAttr.IsIdentity) continue;
strFields.Append(i > 0 ? "," + dfAttr.FieldName : dfAttr.FieldName);
strValues.Append(i > 0 ? "," + "@" + dfAttr.FieldName : "@" + dfAttr.FieldName);
i++;
paraList.Add(new SqlParameter("@" + dfAttr.FieldName, info.GetValue(entity, null)));
}
}
} //格式化SQL拼接語句
string[] args = new string[] { strTableName, strFields.ToString(), strValues.ToString() };
strInsertSQL = string.Format(strInsertSQL, args); //執行結果
int result = 0; try
{ using (SqlConnection conn = GetConnection())
{
conn.Open(); using (SqlCommand cmd = new SqlCommand())
{
cmd.CommandText = strInsertSQL;
cmd.CommandType = CommandType.Text;
cmd.Connection = conn; if (paraList != null)
{ foreach (SqlParameter param in paraList)
{
cmd.Parameters.Add(param);
}
}
result = cmd.ExecuteNonQuery();
}
}
} catch (Exception ex)
{ throw new Exception(ex.ToString());
} //返回影響行數
return result;
} ///
/// 刪除 ///
///
///
///
public static int Delete(string condition) where TEntity : class, new()
{ string strTableName = ""; //表名
string strDeleteSQL = "DELETE FROM {0} WHERE {1}"; //SQL拼接語句 //獲取表名
strTableName = GetTableName(new TEntity()); //格式化SQL拼接語句
string[] args = new string[] { strTableName, condition };
strDeleteSQL = string.Format(strDeleteSQL, args); //執行結果
int result = 0; try
{ using (SqlConnection conn = GetConnection())
{
conn.Open(); using (SqlCommand cmd = new SqlCommand())
{
cmd.CommandText = strDeleteSQL;
cmd.CommandType = CommandType.Text;
cmd.Connection = conn;
result = cmd.ExecuteNonQuery();
}
}
} catch (Exception ex)
{ throw new Exception(ex.ToString());
} //返回影響行數
return result;
} ///
/// 更新 ///
///
///
///
public static int Update(TEntity entity) where TEntity : class
{ string strTableName = ""; //表名
string strUpdateSQL = "UPDATE {0} SET {1} WHERE {2}"; //SQL拼接語句
string strKey = ""; //主鍵
string strWhere = ""; //條件 //獲取表名及主鍵
strTableName = GetTableName(entity);
strKey = GetKey(entity); //獲取更新列表
StringBuilder strSET = new StringBuilder();
ListparaList = new List();
PropertyInfo[] infos = entity.GetType().GetProperties();
DataFieldAttribute dfAttr = null; object[] dfAttrs; int i = 0; foreach (PropertyInfo info in infos)
{
dfAttrs = info.GetCustomAttributes(typeof(DataFieldAttribute), false); if (dfAttrs.Length > 0)
{
dfAttr = dfAttrs[0] as DataFieldAttribute; if (dfAttr is DataFieldAttribute)
{ //條件處理
if (dfAttr.FieldName == strKey)
{
strWhere = strKey + "=" + info.GetValue(entity, null);
} //自增字段不做處理
if (dfAttr.IsIdentity) continue;
strSET.Append(i > 0 ? "," + dfAttr.FieldName + "=@" + dfAttr.FieldName : dfAttr.FieldName + "=@" + dfAttr.FieldName);
i++;
paraList.Add(new SqlParameter("@" + dfAttr.FieldName, info.GetValue(entity, null)));
}
}
} //格式化SQL拼接語句
string[] args = new string[] { strTableName, strSET.ToString(), strWhere };
strUpdateSQL = string.Format(strUpdateSQL, args); //執行結果
int result = 0; try
{ using (SqlConnection conn = GetConnection())
{
conn.Open(); using (SqlCommand cmd = new SqlCommand())
{
cmd.CommandText = strUpdateSQL;
cmd.CommandType = CommandType.Text;
cmd.Connection = conn; if (paraList != null)
{ foreach (SqlParameter param in paraList)
{
cmd.Parameters.Add(param);
}
}
result = cmd.ExecuteNonQuery();
}
}
} catch (Exception ex)
{ throw new Exception(ex.ToString());
} //返回影響行數
return result;
} ///
/// 查詢 ///
///
///
///
public static ListQuery(string condition) where TEntity : class, new()
{ string strTableName = ""; //表名
string strSelectSQL = "SELECT * FROM {0} WHERE {1}"; //SQL拼接語句
Listlist = new List(); //實體列表 //獲取表名
strTableName = GetTableName(new TEntity()); //格式化SQL拼接語句
string[] args = new string[] { strTableName, condition };
strSelectSQL = string.Format(strSelectSQL, args); //獲取實體列表
PropertyInfo[] infos = typeof(TEntity).GetProperties();
DataFieldAttribute dfAttr = null; object[] dfAttrs; try
{ using (SqlConnection conn = GetConnection())
{
conn.Open(); using (SqlCommand cmd = new SqlCommand(strSelectSQL, conn))
{ using (SqlDataReader dr = cmd.ExecuteReader(CommandBehavior.CloseConnection))
{ while (dr.Read())
{
TEntity entity = new TEntity(); foreach (PropertyInfo info in infos)
{
dfAttrs = info.GetCustomAttributes(typeof(DataFieldAttribute), false); if (dfAttrs.Length > 0)
{
dfAttr = dfAttrs[0] as DataFieldAttribute; if (dfAttr is DataFieldAttribute)
{
info.SetValue(entity, dr[dfAttr.FieldName]);
}
}
}
list.Add(entity);
}
}
}
}
} catch (Exception ex)
{ throw new Exception(ex.ToString());
} //返回實體列表
return list;
} ///
/// 根據實體返回表名 ///
///
///
public static string GetTableName(TEntity entity) where TEntity : class
{
Type entityType = entity.GetType(); string strTableName = Convert.ToString(_HashTableName[entityType.FullName]); if (strTableName == "")
{ if (entityType.GetCustomAttributes(typeof(DataTableAttribute), false)[0] is DataTableAttribute dtAttr)
{
strTableName = dtAttr.TableName;
} else
{ throw new Exception(entityType.ToString() + "未設置DataTable特性。");
}
_HashTableName[entityType.FullName] = strTableName;
} return strTableName;
} ///
/// 根據實體返回主鍵 ///
///
///
public static string GetKey(TEntity entity) where TEntity : class
{
Type entityType = entity.GetType(); string strKey = Convert.ToString(_HashKey[entityType.FullName]); if (strKey == "")
{ if (entityType.GetCustomAttributes(typeof(DataTableAttribute), false)[0] is DataTableAttribute dtAttr)
{
strKey = dtAttr.Key;
} else
{ throw new Exception(entityType.ToString() + "未設置DataTable特性。");
}
_HashKey[entityType.FullName] = strKey;
} return strKey;
}
}
}
DBHelper.cs
5、運行測試
新建一個控制檯程序：
using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;using LinkTo.ORM.Model;namespace LinkTo.ORM.Client
{ class Program
{ static void Main()
{ //新增
Person insertPerson = new Person
{
Name = "Hello",
Age = 18,
Gender = "male"
}; int insertResult = DBHelper.Insert(insertPerson);
Console.WriteLine($"共新增了 {insertResult} 條記錄。"); //更新
ListupdateList = DBHelper.Query("Name='Hello'"); int updateResult = 0; if (updateList.Count > 0)
{ foreach (var item in updateList)
{
Person updatePerson = item;
updatePerson.Age = 19;
updateResult += DBHelper.Update(updatePerson);
}
}
Console.WriteLine($"共更新了 {updateResult} 條記錄。"); //查詢
ListselectList = DBHelper.Query("Name='Hello'"); if (selectList.Count > 0)
{ foreach (var item in selectList)
{
Console.WriteLine("person.Name = " + item.Name);
Console.WriteLine("person.Age = " + item.Age);
Console.WriteLine("person.Gender = " + item.Gender);
}
} //刪除
int deleteResult = DBHelper.Delete("Name='Hello'");
Console.WriteLine($"共刪除了 {deleteResult} 條記錄。");
Console.Read();
}
}
}
Program.cs
運行結果以下：
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