public class BaseDal<T> where T:class,new()
{
//此處生成自己的數據實體對象
Entities Db = new Entities();
//**********
/// <summary>
/// 添加
/// </summary>
/// <param name="entity"></param>
/// <returns></returns>
public T AddEntity(T entity)
{
Db.Set<T>().Add(entity);
Db.SaveChanges();
return entity;
}
/// <summary>
/// 刪除
/// </summary>
/// <param name="entity"></param>
/// <returns></returns>
public bool DeleteEntity(T entity)
{
Db.Entry<T>(entity).State = System.Data.Entity.EntityState.Deleted;
return Db.SaveChanges() > 0;
}
/// <summary>
/// 更新
/// </summary>
/// <param name="entity"></param>
/// <returns></returns>
public bool EditEntity(T entity)
{
Db.Entry<T>(entity).State = System.Data.Entity.EntityState.Modified;
return Db.SaveChanges() > 0;
}
/// <summary>
/// 查詢
/// </summary>
/// <param name="whereLambda">System.Linq.Expressions.Expression<Func<UserInfo, bool>>爲參數(lambda表達式樹)類型</param>
/// <returns></returns>
public IQueryable<T> LoadEntities(Expression<Func<T, bool>> whereLambda)
{
return Db.Set<T>().Where<T>(whereLambda);
}
/// <summary>
/// 分頁
/// </summary>
/// <typeparam name="s">方法的泛型類型（由於可參照排序字段數據類型不一樣）</typeparam>
/// <param name="pageIndex">頁碼</param>
/// <param name="pageSize">每頁展示的數據條數</param>
/// <param name="totalCount">數據總條數</param>
/// <param name="whereLambda">用於數據過濾</param>
/// <param name="orderbyLambda">用於數據排序</param>
/// <param name="isAsc">判斷升序或者降序true升序</param>
/// <returns></returns>
public IQueryable<T> LoadPageEntities<s>(int pageIndex, int pageSize, out int totalCount, Expression<Func<T, bool>> whereLambda, Expression<Func<T, s>> orderbyLambda, bool isAsc)
{
var temp = Db.Set<T>().Where<T>(whereLambda);
totalCount = temp.Count();
if (isAsc)//true升序
{
temp = temp.OrderBy<T, s>(orderbyLambda).Skip<T>((pageIndex - 1) * pageSize).Take<T>(pageSize);
}
else
{
temp = temp.OrderBy<T, s>(orderbyLambda).Skip<T>((pageIndex - 1) * pageSize).Take<T>(pageSize);
}
return temp;
}
}
以上代碼在開發過程中可能會存在生成的實體對象即Entity不唯一的問題，即生成多個對象，會操作出錯，因此要考慮實現線程內對象唯一的問題，實現方式在下一篇博客中。