/// <summary>
/// 通过对象的属性名和指定的值搜寻对象集合
/// </summary>
/// <param name="propertyName"></param>
/// <param name="value"></param>
/// <returns></returns>
public static IEnumerable <TEntity> FindBy(string propertyName, object value)
{
var valueType = value.GetType();
if (valueType.IsPrimitive || valueType == typeof(string) || valueType == typeof(Guid))
{
TreeviewContext context = new TreeviewContext();
return(context.GetDatasource <TEntity>().Where(o => Common.GetPropertyValue(o, null) == value));
}
throw new NoSupportCompareTypeException("不支持查询的属性");
}
/// <summary>
/// 分页查询
/// </summary>
/// <param name="pindex"></param>
/// <param name="psize"></param>
/// <param name="orderbyCol"></param>
/// <param name="sortOrder"></param>
/// <param name="total"></param>
/// <returns></returns>
public static IEnumerable <TEntity> FindPage(int pindex, int psize, string orderbyCol, SortOrder sortOrder, out int total)
{
TreeviewContext context = new TreeviewContext();
//return (from e in DataSource orderby GetPropertyValue(e, orderbyCol) select e).Take(psize);
var temp = context.GetDatasource <TEntity>()
.AsEnumerable()
.OrderBy(o => Common.GetPropertyValue(o, orderbyCol));
total = temp.Count();
return(temp.Take(pindex * psize).Skip(psize * (pindex - 1)));
}
/// <summary>
/// 通过一个新的对象来更新旧对象,
/// 具体做法是将新对象中的属性的
/// 值全部复制到旧对象中更新
/// </summary>
/// <param name="newobj"></param>
/// <returns></returns>
public static TEntity Update(TEntity newobj)
{
TreeviewContext context = new TreeviewContext();
var oldObj = context.GetDatasource <TEntity>().FirstOrDefault(o => o.UUID == newobj.UUID);
if (oldObj == null)
{
throw new Exception("未找到需要更新的元素");
}
Common.UpdateObj(ref oldObj, newobj);
if (context.SaveChanges() > 0)
{
return(newobj);
}
return(null);
}
/// <summary>
/// 分页查询
/// </summary>
/// <param name="pindex"></param>
/// <param name="psize"></param>
/// <param name="keyword"></param>
/// <param name="sortColumn"></param>
/// <param name="sortOrder"></param>
/// <param name="total"></param>
/// <returns></returns>
public static IEnumerable <TEntity> FindPage(int pindex, int psize, string keyword, string sortColumn,
SortOrder sortOrder, out int total)
{
TreeviewContext context = new TreeviewContext();
if (string.IsNullOrEmpty(keyword))
{
return(FindPage(pindex, psize, sortColumn, sortOrder, out total));
}
var temp = context.GetDatasource <TEntity>()
.AsEnumerable()
.Where(e => ContansKeyword(e, keyword))
.OrderBy(o => Common.GetPropertyValue(o, sortColumn));
total = temp.Count();
return(temp.Take(pindex * psize).Skip(psize * (pindex - 1)));
}
/// <summary>
/// 删除一个元素,如果元素不存在,则直接返回true
/// </summary>
/// <param name="uuid"></param>
/// <returns>
/// 如果元素不存在,返回true
/// 删除成功返回true
/// 如果删除失败,则返回false
/// </returns>
public static bool Delete(Guid uuid)
{
TreeviewContext context = new TreeviewContext();
var dataSource = context.GetDatasource <TEntity>();
var oldObj = dataSource.FirstOrDefault(o => o.UUID == uuid);
if (oldObj == null)
{
return(true);
}
dataSource.Remove(oldObj);
if (context.SaveChanges() > 0)
{
return(true);
}
return(true);
}
/// <summary>
/// 通过实体属性名称和其对应的值来搜索并且返回
/// 指定页码和条数以及排序规则下的数据集合
/// </summary>
/// <param name="propertyName"></param>
/// <param name="value"></param>
/// <param name="pindex"></param>
/// <param name="psize"></param>
/// <param name="orderbyCol"></param>
/// <param name="sortOrder"></param>
/// <returns></returns>
public static IEnumerable <TEntity> FindPageBy(string propertyName, object value, int pindex, int psize,
string orderbyCol, string sortOrder = "asc")
{
var valueType = value.GetType();
if (valueType.IsPrimitive || valueType == typeof(string) || valueType == typeof(Guid))
{
TreeviewContext context = new TreeviewContext();
return
(context.GetDatasource <TEntity>()
.Where(o => Common.GetPropertyValue(o, null) == value)
.AsEnumerable()
.OrderBy(o => Common.GetPropertyValue(o, orderbyCol))
.Take(pindex * psize)
.Skip(psize * (pindex - 1)));
}
throw new NoSupportCompareTypeException("不支持查询的属性");
}
/// <summary>
/// 添加一个新的对象,并且该函数会给对象自动赋予UUID,
/// 如果外部已经有生成一个UUID,执行该函数后UUID会
/// 被重写,如果数据插入成功,将返回该对象,如果出错,那么
/// 则返回一个空对象.
/// </summary>
/// <param name="e"></param>
/// <returns></returns>
public static TEntity Add(TEntity e)
{
if (Exists(e))
{
throw new EntityExistsException("Entity has exists.");
}
if (e.UUID == Guid.Empty)
{
e.UUID = Guid.NewGuid();
}
TreeviewContext context = new TreeviewContext();
context.GetDatasource <TEntity>().Add(e);
int flag = context.SaveChanges();
if (flag > 0)
{
return(e);
}
return(null);
}
/// <summary>
/// 通过UUID查找数据集中的某一个对象
/// 没找到则返回null
/// </summary>
/// <param name="uuid"></param>
/// <returns></returns>
public static TEntity Find(Guid uuid)
{
TreeviewContext context = new TreeviewContext();
return(context.GetDatasource <TEntity>().FirstOrDefault(o => o.UUID == uuid));
}
/// <summary>
/// 获取数据集中的所有元素.
/// </summary>
/// <returns></returns>
public static IEnumerable <TEntity> FindAll()
{
TreeviewContext context = new TreeviewContext();
return(context.GetDatasource <TEntity>());
}
/// <summary>
/// 获取数据仓储中某个类型的对象的总条目数量
/// </summary>
/// <returns></returns>
public static int Count()
{
TreeviewContext context = new TreeviewContext();
return(context.GetDatasource <TEntity>().Count());
}
/// <summary>
/// 检查数据仓储中是否存在某个类型的对象
/// </summary>
/// <returns></returns>
public static bool HasData()
{
TreeviewContext context = new TreeviewContext();
return(context.GetDatasource <TEntity>().Any());
}
/// <summary>
/// 查看元素是否已经存在,默认通过UUID
/// 来判断元素是否有重复
/// </summary>
/// <param name="entity"></param>
/// <returns></returns>
public static bool Exists(TEntity entity)
{
TreeviewContext context = new TreeviewContext();
return(context.GetDatasource <TEntity>().Any(e => e.UUID == entity.UUID));
}