/// <summary>
/// 从DataTable获取一个实体列表
/// </summary>
/// <param name="table">DataTable实例</param>
/// <remarks>
/// <list type="bullet">
/// <item><description>建议不要直接从DataTable返回实体,而是通过CPQuery或者StoreProcedure返回实体</description></item>
/// </list>
/// </remarks>
/// <example>
/// <para>下面的代码演示了从DataTable获取一个实体列表的用法</para>
/// <code>
/// <![CDATA[
/// //存储过程中包含两个SELECT语句,返回两个结果集
/// DataSet ds = StoreProcedure.Create("usp_GetTestDataType").FillDataSet();
///
/// foreach( DataTable table in ds2.Tables ) {
///
/// //将DataTable转换为实体集合
/// List<TestDataType> list = table.ToList<TestDataType>();
///
/// }
/// ]]>
/// </code>
/// </example>
/// <typeparam name="T">实体类型</typeparam>
/// <exception cref="ArgumentNullException">table参数为null</exception>
/// <returns>实体列表</returns>
public static List <T> ToList <T>(this DataTable table) where T : class, new()
{
if (table == null)
{
throw new ArgumentNullException("table");
}
Type type = typeof(T);
TypeDescription description = TypeDescriptionCache.GetTypeDiscription(type);
if (description.ExecuteFunc != null)
{
try
{
return(description.ExecuteFunc(10, new object[] { table }) as List <T>);
}
catch (System.Exception ex)
{
//这里不希望调用者看到代码生成器产生的代码结构,于是在这里抛出捕获到的异常
throw ex;
}
}
else if (type.IsSubclassOf(typeof(BaseEntity)))
{
throw new InvalidProgramException(
string.Format("类型 {0} 找不到ToList的操作方法，请确认已将实体类型定义在*.Entity.dll结尾的程序集中，且不是嵌套类，并已提供无参的构造函数。", type.FullName));
}
else
{
return(DbHelper.ToList <T>(table, description));
}
}
internal static T ToSingle <T>(OracleCommand cmd, string connectionString) where T : class, new()
{
Type type = typeof(T);
TypeDescription description = TypeDescriptionCache.GetTypeDiscription(type);
using (ConnectionScope scope = new ConnectionScope(connectionString))
{
return(scope.Current.ExecuteCommand <T>(cmd, p => {
using (OracleDataReader reader = p.ExecuteReader())
{
if (description.ExecuteFunc != null)
{
return description.ExecuteFunc(2, new object[] { reader }) as T;
}
else if (type.IsSubclassOf(typeof(BaseEntity)))
{
throw BaseEntity.GetNonStandardExecption(type);
}
else
{
return ToSingle <T>(reader, description);
}
}
}));
}
}
/// <summary>
/// 此API不宜在项目代码中调用，仅供内部使用。
/// </summary>
public void TrackChange()
{
TypeDescription description = TypeDescriptionCache.GetTypeDiscription(GetType());
if (description.ExecuteFunc == null)
{
throw GetNonStandardExecption(this.GetType());
}
bakObject = description.ExecuteFunc(13, new object[] { this }) as BaseEntity;
}
/// <summary>
/// 获取查询SQL
/// </summary>
/// <returns>查询SQL</returns>
public virtual string GetSelectSQL()
{
TypeDescription description = TypeDescriptionCache.GetTypeDiscription(GetType());
if (description.ExecuteFunc == null)
{
throw GetNonStandardExecption(this.GetType());
}
try
{
return(description.ExecuteFunc(15, null) as string);
}
catch (System.Exception ex)
{
//这里不希望调用者看到代码生成器产生的代码结构,于是在这里抛出捕获到的异常
throw ex;
}
}
internal CPQuery GetCPQuery(int flag, params object[] parameters)
{
TypeDescription description = TypeDescriptionCache.GetTypeDiscription(GetType());
if (description.ExecuteFunc == null)
{
throw GetNonStandardExecption(this.GetType());
}
try
{
return(description.ExecuteFunc(flag, parameters) as CPQuery);
}
catch (System.Exception ex)
{
//这里不希望调用者看到代码生成器产生的代码结构,于是在这里抛出捕获到的异常
throw ex;
}
}
/// <summary>
/// 将泛类型集合List类转换成DataTable
/// </summary>
/// <param name="list">泛类型集合</param>
/// <returns></returns>
public static DataTable ToDataTable <T>(this List <T> entitys) where T : class, new()
{
//检查实体集合不能为空
if (entitys == null)
{
throw new ArgumentNullException("需转换的集合为空");
}
//取出第一个实体的所有Propertie
Type entityType = typeof(T);
TypeDescription description = TypeDescriptionCache.GetTypeDiscription(entityType);
Dictionary <string, DbMapInfo> dict = description.MemberDict;
//生成DataTable的structure
//生产代码中，应将生成的DataTable结构Cache起来，此处略
DataTable dt = new DataTable();
foreach (string key in dict.Keys)
{
Type colType = dict[key].PropertyInfo.PropertyType;
if ((colType.IsGenericType) && (colType.GetGenericTypeDefinition() == typeof(Nullable <>)))
{
colType = colType.GetGenericArguments()[0];
}
dt.Columns.Add(key, colType);
}
//将所有entity添加到DataTable中
foreach (T entity in entitys)
{
object[] entityValues = new object[dict.Keys.Count];
int i = 0;
foreach (string key in dict.Keys)
{
entityValues[i] = dict[key].PropertyInfo.FastGetValue(entity);
i++;
}
dt.Rows.Add(entityValues);
}
return(dt);
}
//private string GeneratorCode(TypesAndReferences threadParam)
//{
// //测试ERP258系统,1253个实体类,5线程编译,每线程的StringBuilder长度数据如下:
// //3826393,4451978,3653788,4433206,4545317
// //根据以上数字,初始值设置为1024*1024*5
// StringBuilder sb = new StringBuilder(1024 * 1024 * 5);
// // 生成命名空间和命名空间的引用
// sb.AppendLine(CodeGenerator.GetCodeHeader());
// // 生成一个工具类
// sb.AppendLine(CodeGenerator.GetCodeUtil());
// // 为每个数据实体类型生成数据访问代码
// foreach (Type type in threadParam.EntityTypes)
// {
// CodeGenerator generator = new CodeGenerator(type);
// // 数据访问代码的类型名称根据数据实体名称得到，具体生成方法请参考下面这行代码。
// string className = "CodeDom_" + type.FullName.Replace(".", "_");
// // 生成数据访问代码。
// string code = generator.GetCode(className);
// sb.AppendLine(code);
// }
// sb.Append("}");
// return sb.ToString();
//}
//private Assembly CompilerCode(string code, string[] referenceAssemblies)
//{
// CompilerParameters cp = new CompilerParameters();
// cp.GenerateExecutable = false;
// cp.GenerateInMemory = true;
// for (int i = 0; i < referenceAssemblies.Length; i++)
// cp.ReferencedAssemblies.Add(referenceAssemblies[i]);
// using (CSharpCodeProvider csProvider = new CSharpCodeProvider())
// {
// // 编译代码
// CompilerResults cr = csProvider.CompileAssemblyFromSource(cp, code);
// // 检查是否发生编译错误。
// if (cr.Errors != null && cr.Errors.HasErrors)
// {
// throw new CompileException { Code = code, CompilerResult = cr };
// }
// return cr.CompiledAssembly;
// }
//}
private void CreateDelegate(List <Type> types, Assembly assembly)
{
foreach (Type type in types)
{
// 从编译结果中查找类型名称。
string className = "_Tool.AutoGenerateCode.CodeDom_" + type.FullName.Replace(".", "_");
// 从编译结果中查找类型
Type targetType = assembly.GetType(className);
// 从找到的类型中查找供外面调用的接口方法
MethodInfo methodExecute = targetType.GetMethod("Execute", BindingFlags.Static | BindingFlags.Public);
// 生成调用委托
Func <int, object[], object> executeFunc = Delegate.CreateDelegate(typeof(Func <int, object[], object>), methodExecute) as Func <int, object[], object>;
// 保存委托。
TypeDescription description = new TypeDescription()
{
ExecuteFunc = executeFunc
};
TypeDescriptionCache.SaveComplieResult(type, description);
}
}
