/// <summary>
/// 与逻辑运算
/// </summary>
/// <typeparam name="T">实体类型</typeparam>
/// <param name="expLeft">表达式1</param>
/// <param name="propertyName">属性名称</param>
/// <param name="value">属性值</param>
/// <param name="operator">操作符</param>
/// <exception cref="MissingFieldException"></exception>
/// <exception cref="NotSupportedException"></exception>
/// <returns></returns>
public static Expression <Func <T, bool> > And <T>(this Expression <Func <T, bool> > expLeft,
string propertyName, object value, SQLOperator @operator)
{
var expRight = SQLPredicate.Create <T>(propertyName, value, @operator);
return(expLeft.And(expRight));
}
/// <summary>
/// 转换为Or连接的谓词筛选表达式
/// </summary>
/// <param name="falseWhenNull">当生成的表达式为null时返回false表达式</param>
/// <returns></returns>
public Expression <Func <T, bool> > ToOrPredicate(bool falseWhenNull = true)
{
if (Items.Count == 0)
{
return(falseWhenNull ? SQLPredicate.False <T>() : null);
}
return(Items
.Select(item => item.ToPredicate())
.Aggregate((left, right) => left.Or(right)));
}
/// <summary>
/// 与逻辑运算
/// </summary>
/// <typeparam name="T">实体类型</typeparam>
/// <typeparam name="TKey">属性类型</typeparam>
/// <param name="expLeft">表达式1</param>
/// <param name="keySelector">属性选择</param>
/// <param name="value">值</param>
/// <param name="operator">操作符</param>
/// <exception cref="ArgumentNullException"></exception>
/// <exception cref="NotSupportedException"></exception>
/// <returns></returns>
public static Expression <Func <T, bool> > And <T, TKey>(this Expression <Func <T, bool> > expLeft,
Expression <Func <T, TKey> > keySelector, TKey value, SQLOperator @operator)
{
if (keySelector is null)
{
throw new ArgumentNullException(nameof(keySelector));
}
var expRight = SQLPredicate.Create(keySelector, value, @operator);
return(expLeft.And(expRight));
}
/// <summary>
/// 与逻辑运算
/// </summary>
/// <typeparam name="T">实体类型</typeparam>
/// <typeparam name="TKey">属性类型</typeparam>
/// <param name="expLeft">表达式1</param>
/// <param name="keySelector">属性选择</param>
/// <param name="values">值</param>
/// <exception cref="ArgumentNullException"></exception>
/// <returns></returns>
public static Expression <Func <T, bool> > AndNotIn <T, TKey>(this Expression <Func <T, bool> > expLeft,
Expression <Func <T, TKey> > keySelector, IEnumerable <TKey> values)
{
if (keySelector is null)
{
throw new ArgumentNullException(nameof(keySelector));
}
// ReSharper disable once PossibleMultipleEnumeration
if (values is null || values.Any() == false)
{
return(expLeft);
}
// ReSharper disable once PossibleMultipleEnumeration
var expRight = SQLPredicate.CreateAndNotEqual(keySelector, values);
return(expLeft.And(expRight));
}
/// <summary> /// 转换为谓词筛选表达式 /// </summary> /// <exception cref="NotSupportedException"></exception> /// <returns></returns> public Expression <Func <T, bool> > ToPredicate() => SQLPredicate.Create <T>(Member, Value, Operator);