/// <summary>
/// 创建二元操作表达式。
/// </summary>
/// <param name="kind">二元操作种类。</param>
/// <param name="left">左端表达式。</param>
/// <param name="right">右端表达式。</param>
/// <param name="type">两端操作数据类型。</param>
public DbBinaryExpression(EBinaryKind kind, DbExpression left, DbExpression right, Type type)
{
Kind = kind;
Left = left;
Right = right;
ClrType = type;
}
/// <summary>
/// 初始化二元逻辑运算。
/// </summary>
/// <param name="context">生成上下文。生成上下文。</param>
/// <param name="kind">逻辑运算种类。</param>
public BinaryLogicalFragment(GenerateContext context, EBinaryKind kind)
: base(context)
{
if (kind == EBinaryKind.AndAlso || kind == EBinaryKind.OrElse)
{
Kind = kind;
}
else
{
throw new ArgumentException(Res.ExceptionBinaryLogicalKind, nameof(kind));
}
}
/// <summary>
/// 向指定的表达式语句片段合并多个<see cref="IExpressionFragment"/>片段。
/// </summary>
/// <param name="target">目标语句片段</param>
/// <param name="kind">逻辑操作符种类。</param>
/// <param name="fragments">合并的语句片段集合。</param>
/// <returns>合并结果。</returns>
public static ILogicFragment Merge(this IExpressionFragment target, EBinaryKind kind, IEnumerable <IExpressionFragment> fragments)
{
var current = target as BinaryLogicalFragment;
if (!fragments.Any())
{
throw new ArgumentException(Res.ExceptionMergeFragmentIsNotEmpty, nameof(fragments));
}
foreach (var fragment in fragments)
{
if (current == null)
{
if (fragment is BinaryLogicalFragment binary && binary.Kind == kind)
{
current = binary;
current.Expressions.Insert(0, target);
}
else
{
current = new BinaryLogicalFragment(target.Context, kind);
current.Expressions.Add(target);
current.Expressions.Add(fragment);
}
}
/// <summary>
/// 初始化二元运算。
/// </summary>
/// <param name="context">生成上下文。</param>
/// <param name="kind">二元运算种类。</param>
public BinaryFragment(GenerateContext context, EBinaryKind kind)
: base(context)
{
Kind = kind;
}
/// <summary>
/// 合并多个<see cref="IExpressionFragment"/>片段为一个逻辑判断语句片段。
/// </summary>
/// <param name="fragments">合并的语句片段集合。</param>
/// <param name="kind">逻辑操作符种类。</param>
/// <returns>合并结果。</returns>
public static ILogicFragment Merge(this IEnumerable <IExpressionFragment> fragments, EBinaryKind kind = EBinaryKind.AndAlso)
{
var array = fragments.ToArray();
if (array.Length == 1)
{
return(array[0] as ILogicFragment);
}
var other = new IExpressionFragment[array.Length - 1];
Array.Copy(array, 1, other, 0, other.Length);
return(Merge(array[0], kind, other));
}
/// <summary> /// 合并多个<see cref="BinaryFragment"/>片段为一个逻辑判断语句片段。 /// </summary> /// <param name="fragments">合并的语句片段集合。</param> /// <param name="kind">逻辑操作符种类。</param> /// <returns>合并结果。</returns> public static ILogicFragment Merge(this IEnumerable <BinaryFragment> fragments, EBinaryKind kind = EBinaryKind.AndAlso) => Merge(fragments, kind);