/// <summary>
/// 刷新一个已存在的实体(如果一个实体类的属性的值是旧的，可以使用此方法从数据库中刷新值)
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="entity"></param>
/// <returns></returns>
public static TEntity RefreshEntity <TEntity>(TEntity entity) where TEntity : SQLEntity
{
var keyContext = EntityParser.GetKey(typeof(TEntity));
var keyName = keyContext.KeyName;
var sql = SqlBuilder.SelectSQL(typeof(TEntity), string.Format("{0} = @{0}", keyName));
return(SQLServerHelper.FirstOrDefault((reader) =>
{
return FilldEntity <TEntity>(reader, entity);
}, sql, new SqlParameter("@" + keyName, keyContext.Key.GetValue(entity, null))));
}
/// <summary>
/// 使用指定的where条件和参数从数据库获取多个实体对象
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="where">where条件，也可以具有order</param>
/// <param name="pms">参数</param>
/// <returns></returns>
public static List <TEntity> Many <TEntity>(string where, string order, params SqlParameter[] pms) where TEntity : SQLEntity
{
var sql = new StringBuilder();
sql.Append(SqlBuilder.SelectSQL(typeof(TEntity), where));
if (!string.IsNullOrEmpty(order))
{
sql.AppendFormat("ORDER BY {0}", order);
}
return(SQLServerHelper.GetMany((reader) =>
{
return FilldEntity <TEntity>(reader);
}, sql.ToString(), pms));
}
/// <summary>
/// 将实体实例的属性的值更新到数据库中，必须指定主键
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="entity"></param>
/// <param name="updateToEntity"></param>
/// <returns></returns>
public static TEntity Update <TEntity>(TEntity entity, bool updateToEntity = true) where TEntity : SQLEntity
{
if (entity.EntityState == EntityState.NotInitialized)
{
throw new Exception("要更新的实体尚未初始化");
}
else if (entity.EntityState == EntityState.NotChanged)
{
return(entity);
}
else
{
var entityType = typeof(TEntity);
var key = EntityParser.GetKey(entityType); //找到主键属性
if (key == null)
{
throw new Exception("在实体类中没有找主键属性");
}
List <SqlParameter> parameters = new List <SqlParameter>();
var tableName = EntityParser.GetTableName(entityType);
StringBuilder update = new StringBuilder();
update.AppendFormat("UPDATE [{0}] SET ", tableName);
var flags = false;
foreach (var propertyName in entity) //遍历更改的属性
{
if (propertyName == key.PropertyName)
{
continue;
}
var propertyInfo = entityType.GetProperty(propertyName);
if (propertyInfo == null || EntityParser.IsIgnore(propertyInfo)) //如果找不到属性或不映射到数据库
{
continue;
}
var sqlPair = SqlBuilder.ColumnSqlForUpdate(entity, propertyInfo, parameters); //获取更新列值的sql语句
if (string.IsNullOrEmpty(sqlPair))
{
continue;
}
else
{
string columnName = EntityParser.GetColumnName(propertyInfo);
update.AppendFormat("{0} = {1}, ", columnName, sqlPair);
flags = true;
}
}
if (flags)
{
update.Remove(update.Length - 2, 2).AppendFormat(" ");
}
else
{
return(entity);
}
update.AppendFormat(" WHERE {0} = @{0}", key.KeyName);
var keyValue = key.Key.GetValue(entity, null); //获取主键的值
parameters.Add(new SqlParameter("@" + key.PropertyName, keyValue));
SQLServerHelper.ExecuteNonQuery(update.ToString(), parameters.ToArray()); //更新到数据库
entity.EntityState = EntityState.NotChanged; //未更改
if (updateToEntity)
{
//SingleByKey(keyValue, entity); //从数据库刷新属性
RefreshEntity(entity);
}
}
return(entity);
}
/// <summary>
/// 向数据库中插入一个实体并返回实体类的主键的值，并从数据库中刷新实体的所有值
/// </summary>
/// <typeparam name="TKey"></typeparam>
/// <typeparam name="TEntity"></typeparam>
/// <param name="entity">要插入到数据库的实体类的实例</param>
/// <returns></returns>
public static TEntity Insert <TEntity>(TEntity entity) where TEntity : SQLEntity
{
var entityType = typeof(TEntity);
List <ColumnContext> contexts;
if (!insertCache.TryGetValue(entityType, out contexts))
{
contexts = new List <ColumnContext>();
foreach (var propertyInfo in entityType.GetProperties())
{
if (EntityParser.IsIgnore(propertyInfo))
{
continue;
}
var config = EntityParser.GetColumnConfig(propertyInfo);
var context = new ColumnContext()
{
Config = config,
PropertyInfo = propertyInfo,
PropertyName = propertyInfo.Name,
ColumnName = EntityParser.GetColumnName(propertyInfo)
};
contexts.Add(context);
}
insertCache.Add(entityType, contexts);
}
List <SqlParameter> parameters = new List <SqlParameter>();
foreach (var context in contexts)
{
if (context.Config.UsePropertyForInsert)
{
var valueExpression = "@" + context.PropertyName;
var propertyValue = context.PropertyInfo.GetValue(entity, null);
if (context.Config.DBType == DBType.PropertyType) //如果直接用属性
{
parameters.Add(new SqlParameter(valueExpression, propertyValue));
}
else //如果要转换类型
{
propertyValue = EntityParser.ConvertPropertyValue(context.PropertyInfo, propertyValue, context.Config.DBType);
parameters.Add(new SqlParameter(valueExpression, propertyValue));
}
}
}
var keyContext = EntityParser.GetKey(entityType); //寻找主键特性
object key;
string sql = SqlBuilder.InsertSQL(entityType);
if (keyContext.KeyConfig.UsePropertyForInsert) //如果使用属性的值插入到数据库
{
SQLServerHelper.ExecuteNonQuery(sql, parameters.ToArray());
key = keyContext.Key.GetValue(entity, null);
}
else
{
key = SQLServerHelper.GetSingle(sql, parameters.ToArray()); //插入并获取主键的值
}
var se = entity as SQLEntity;
if (se != null)
{
se.EntityState = EntityState.NotInitialized; //未初始化
}
string selectSQL = SqlBuilder.SelectSQL(typeof(TEntity), string.Format("{0} = @{0}", keyContext.PropertyName));
SQLServerHelper.FirstOrDefault((reader) =>
{
return(FilldEntity <TEntity>(reader, entity));
}, selectSQL, new SqlParameter("@" + keyContext.PropertyName, key)); //从数据库中刷新实体
if (se != null)
{
se.EntityState = EntityState.NotChanged; //未修改
}
return(entity);
}
/// <summary>
/// 根据指定的条件删除多个实体
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="where">条件</param>
/// <param name="pms">参数</param>
public static void Delete <TEntity>(string where, params SqlParameter[] pms) where TEntity : SQLEntity
{
var sql = SqlBuilder.DeleteSQL(EntityParser.GetTableName(typeof(TEntity)), where);
SQLServerHelper.ExecuteNonQuery(sql, pms);
}
