using System; using System.Collections.Generic; using System.Linq; using System.Text; using Signum.Utilities; using System.Runtime.Serialization; using System.Reflection; using System.Collections.Specialized; using Signum.Entities.Properties; using Signum.Utilities.DataStructures; using Signum.Entities.Reflection; using System.ComponentModel; using System.Linq.Expressions; using Signum.Utilities.Reflection; using Signum.Utilities.ExpressionTrees; using Signum.Services; namespace Signum.Entities { [Serializable] public abstract class IdentifiableEntity : ModifiableEntity, IIdentifiable { internal int? id = null; //primary key protected internal string toStr; //no value for new entities [HiddenProperty, Description("Id")] public int Id { get { if (id == null) throw new InvalidOperationException("{0} is new and has no Id".Formato(this.GetType().Name)); return id.Value; } internal set { id = value; } } [HiddenProperty] [Description("Id")] public int? IdOrNull { get { return id; } } [HiddenProperty] public string ToStr { get { return toStr; } protected set { Set(ref toStr, value, () => ToStr); } } [Ignore] bool isNew = true; [HiddenProperty] public bool IsNew { get { return isNew; } internal set { isNew = value; } } protected bool SetIfNew<T>(ref T field, T value, Expression<Func<T>> property) { if (EqualityComparer<T>.Default.Equals(field, value)) return false; if (!IsNew) { PropertyInfo pi = ReflectionTools.BasePropertyInfo(property); throw new InvalidOperationException("Attempt to modify '{0}' when the entity is not new".Formato(pi.Name)); } return base.Set<T>(ref field, value, property); } protected internal override void PreSaving(ref bool graphModified) { base.PreSaving(ref graphModified); toStr = ToString(); } public override string ToString() { return BaseToString(); } internal string BaseToString() { return "{0} ({1})".Formato(GetType().Name, id.HasValue ? id.ToString() : Resources.New); } public override bool Equals(object obj) { if(obj == this) return true; if(obj == null) return false; IdentifiableEntity ident = obj as IdentifiableEntity; if (ident != null && ident.GetType() == this.GetType() && this.id != null && this.id == ident.id) return true; return false; } public virtual string IdentifiableIntegrityCheck() { return GraphExplorer.IdentifiableIntegrityCheck(GraphExplorer.FromRootIdentifiable(this)); } public override int GetHashCode() { return id == null ? base.GetHashCode() : StringHashEncoder.GetHashCode32(GetType().FullName) ^ id.Value; } } public interface IIdentifiable : INotifyPropertyChanged, IDataErrorInfo, ICloneable, IRootEntity { int Id { get; } int? IdOrNull { get; } string ToStr { get; } bool IsNew { get; } } public interface IRootEntity { } }
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