internal Delete(XContext context, T entity)
: this(context)
{
if (entity == null)
{
throw Error.ArgumentNullException(nameof(entity));
}
var condition = MapperConfig.GetKeysExpression <T>(entity);
if (condition != null)
{
this.Where(condition);
}
}
/// <summary>
/// 根据主键值获取实体对象
/// </summary>
/// <typeparam name="T">查询结果实体类型</typeparam>
/// <param name="keys">主键值</param>
/// <returns>返回主键等于主键值的实体对象，没有返回null</returns>
public T GetByKey <T>(params object[] keys)
{
if (keys.IsNullOrEmpty())
{
return(default(T));
}
var keyCondition = MapperConfig.GetKeysExpression <T>(keys);
if (keyCondition != null)
{
return(GetFirstOrDefault(keyCondition));
}
return(default(T));
//var keyMeta = MapperConfig.GetKeyMetas<T>();
//if (keyMeta == null)
//{
// throw Error.Exception("没有为模型" + typeof(T).FullName + "指定主键。");
//}
//if (keys.Length != keyMeta.Length)
//{
// return default(T);
//}
//LambdaExpression body = null;
//ParameterExpression parameter = null;
//for (var i = 0; i < keyMeta.Length; i++)
//{
// var meta = keyMeta[i];
// if (meta.Expression is LambdaExpression exp)
// {
// parameter = exp.Parameters.FirstOrDefault();
// var keyExp = Expression.Constant(keys[i]);
// var mem = exp.Body.ChangeType(keyExp.Type);
// var condition = Expression.Equal(keyExp, mem);
// var innerLambda = Expression.Lambda(condition, parameter);
// body = body.AndAlso(innerLambda);
// }
//}
//if (body == null)
//{
// return default(T);
//}
//var lambda = Expression.Lambda<Func<T, bool>>(body.Body, parameter);
//return GetFirstOrDefault(lambda);
}
internal Delete(XContext context, params object[] keys)
: this(context)
{
if (keys.IsNullOrEmpty())
{
throw Error.ArgumentNullException(nameof(keys));
}
var condition = MapperConfig.GetKeysExpression <T>(keys);
if (condition != null)
{
this.Where(condition);
}
}
private void AddConditionByKey(T oldEntity)
{
var condition = MapperConfig.GetKeysExpression <T>(oldEntity);
if (condition != null)
{
this.Where(condition);
this.hasKeyWhere = true;
}
//if (exp != null)
//{
// var val = exp.Compile().DynamicInvoke(oldEntity);
// var keyExp = Expression.Constant(val);
// var mem = exp.Body.ChangeType(keyExp.Type);
// var newExp = Expression.Equal(mem, keyExp);
// var lambda = Expression.Lambda<Func<T, bool>>(newExp, exp.Parameters);
// this.Where(lambda);
// this.hasKeyWhere = true;
//}
//else
//{
// throw Error.Exception("没有为类型 " + tableMeta.Type.Name + " 指定主键。");
//}
}