Programming with iBATIS DataMapper: The .NET API

DataMapper API 提供四个核心方法

    1. build a SqlMapper instance from a configuration file

    2. execute an update query (including insert and delete).

    3. execute a select query for a single object

    4. execute a select query for a list of objects

4.4.1. Building a SqlMapper Instance

[C#]
using IBatisNet.Common.Utilities;
using IBatisNet.DataMapper;
using IBatisNet.DataMapper.Configuration;

namespace IBatisNet.DataMapper
{
 public class Mapper
 {
  private static volatile ISqlMapper _mapper = null;

  protected static void Configure (object obj)
  {
   _mapper = null;
  }

  protected static void InitMapper()
  {
   ConfigureHandler handler = new ConfigureHandler(Configure);
   DomSqlMapBuilder builder = new DomSqlMapBuilder();
   _mapper = builder.ConfigureAndWatch(handler);
  }

  public static ISqlMapper Instance()
  {
   if (_mapper == null)
   {
    lock (typeof (SqlMapper))
    {
     if (_mapper == null) // double-check
     { 
      InitMapper();
     }
    }
   }
   return _mapper;
  }
  
  public static ISqlMapper Get()
  {
   return Instance();
  }
 }
}
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程序中使用 ISqlMapper实例时，只需调用ISqlMapper mapper = Mapper.Instance();

DomSqlMapBuilder 加载SqlMap.config创建SqlMapper实例。DomSqlMapBuilder.ConfigureAndWatch()方法监视配置文件，有修改自动重新加载配置，而不需要编译，重启程序。（动态重载需要配置文件能被文件系统访问）

4.4.1.1. Multiple Databases

如果一个程序中需要访问多个数据库，创建新的SqlMapp.config和Mapper 类，用来创建另一个ISqlMapper实例。

ISqlMapper sqlServer = SqlServerMapper.Get();
ISqlMapper access = AccessMapper.Get();

4.4.1.2. DomSqlMapBuilder Configuration Options

配置文件设置相对路径或绝对路径

1. SqlMapper Configuration through an absolute or relative file path
/* Configure a SqlMapper from a file path.
   Uses a relative resource path from your application root 
   or an absolute file path such as "file:\\c:\dir\a.config" */
ISqlMapper mapper = builder.Configure(strPath);

mapper = builder.Configure(ConfigurationSettings.AppSettings["rootPath"]+"SqlMap.config");

2. SqlMapper Configuration with a FileInfo or Uri instance
/* Configure a SqlMapper with FileInfo. */
FileInfo aFileInfo = someSupportClass.GetDynamicFileInfo();
ISqlMapper mapper = builder.Configure(aFileInfo);

/* Configure a SqlMapper through a Uri. */
Uri aUri = someSupportClass.GetDynamicUri();
ISqlMapper anotherMapper = builder.Configure(aUri);

3.SqlMapper Configuration with an XmlDocument or Stream
/* Configure a SqlMapper with an XmlDocument */
XmlDocument anXmlDoc = someSupportClass.GetDynamicXmlDocument();
ISqlMapper mapper = builder.Configure(anXmlDoc);

/* Configure a SqlMapper from a stream. */
Stream aStream = someSupportClass.GetDynamicStream();
ISqlMapper anotherMapper = builder.Configure(aStream);
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Mapper ConfigureHandler delegate

...
  protected static void Configure (object obj)
  {
   _mapper = null;
  }

  protected static void InitMapper()
  {
   ConfigureHandler handler = new ConfigureHandler(Configure);
   DomSqlMapBuilder builder = new DomSqlMapBuilder();
   _mapper = builder.ConfigureAndWatch(handler);
  }
...
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给DomSqlMapBuilder 传递一个委托ConfigureHandler 用来重置应用程序的SqlMapper实例。

4.4.1.3. DomSqlMapBuilder : Advanced settings

4.4.2. Exploring the DataMapper API through the SqlMapper

4.4.2.1. Insert, Update, Delete

public object Insert(string statementName,
                     object parameterObject);
public int Update(string statementName,
                  object parameterObject);
public int Delete(string statementName,
                  object parameterObject);
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<insert> 通过嵌套<selectKey>返回自动生成的主键，不设置<selectKey>返回null

update和insert 返回受影响行数

4.4.2.2. QueryForObject

public object QueryForObject(string statementName,
                             object parameterObject);
public object QueryForObject(string statementName, 
                             object parameterObject,
                             object resultObject);

public T QueryForObject<T>(string statementName, object parameterObject);
public T QueryForObject<T>(string statementName, object parameterObject, T resultObject);
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4.4.2.3. QueryForList

public IList QueryForList(string statementName,
                          object parameterObject);
public void QueryForList(string statementName,
                         object parameterObject,
                         IList resultObject);
public IList QueryForList(string statementName,
                          object parameterObject,
                          int skipResults,
                          int maxResults);

public IList<T> QueryForList<T>(string statementName, object parameterObject);
public void QueryForList<T>(string statementName, 
                                  object parameterObject, 
                                  IList<T> resultObject);
public IList<T> QueryForList<T>(string statementName, 
                                            object parameterObject,
                                            int skipResults, int maxResults);
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4.4.2.4. QueryWithRowDelegate

public delegate void RowDelegate(object obj,
                                 IList list);

public IList QueryWithRowDelegate(string statementName,
                                  object parameterObject, 
                                  RowDelegate rowDelegate);

public IList<T> QueryWithRowDelegate<T>(string statementName, object parameterObject, 
                                SqlMapper.RowDelegate<T> rowDelegate);
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public delegate void RowDelegate(object obj, object parameterObject, IList list); //obj结果集的每一行，object传入参数，list结果集，在遍历每一行的时候将结果添加到list，不添加就不返回

4.4.2.5.  QueryForMapWithRowDelegate

public delegate void DictionaryRowDelegate(object key, 
                                           object value, 
                                           object parameterObject, 
                                           IDictionary dictionary);

public IDictionary QueryForMapWithRowDelegate(string statementName,
                                              object parameterObject, 
                                              string keyProperty, 
                                              string valueProperty, 
                                              DictionaryRowDelegate rowDelegate);
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4.4.2.6. QueryForPaginatedList

The method PaginatedList has been made as obsolete and will not be supported in future version.

4.4.2.7. QueryForDictionary, QueryForMap

public IDictionary QueryForDictionary(string statementName,
                                      object parameterObject,
                                      string keyProperty)
public IDictionary<K, V> QueryForDictionary<K, V>(string statementName, 
                                      object parameterObject, 
                                      string keyProperty);
public IDictionary QueryForDictionary(string statementName,
                                      object parameterObject,
                                      string keyProperty,
                                      string valueProperty)
public IDictionary<K, V> QueryForDictionary<K, V>(string statementName, 
                                     object parameterObject, 
                                      string keyProperty, 
                                      string valueProperty);

public IDictionary QueryForMap(string statementName,
                               object parameterObject, 
                               string keyProperty)
public IDictionary QueryForMap(string statementName, 
                               object parameterObject, 
                               string keyProperty, 
                               string valueProperty)
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keyProperty：指定该列值为字典的key，指定了valueProperty则字典value为valueProperty对应列的值，如果不指定valueProperty则字典value为行实体对象。

 

posted @ 2020-03-29 02:01  vvf  阅读(158)  评论(0)  编辑  收藏  举报