When selecting a customer on the Case screen. How can the system automatically add previous historical Cases of the same customer on the "RELATED CASES" TAB ?

Hi @nhatnghetinh,

Glad that helped.!

To be able to add the cases on the go, in the CRCaseMaint extension you can try override the caseRefs Data Handler to match your requirement.

protected virtual IEnumerable caseRefs()
		{
			var currentCaseCd = Case.Current.With(_ => _.CaseCD);
			if (currentCaseCd == null) yield break;

			var ht = new HybridDictionary();
			foreach (CRCaseReference item in
				PXSelect<CRCaseReference,
					Where<CRCaseReference.parentCaseCD, Equal<Required<CRCaseReference.parentCaseCD>>>>.
				Select(this, currentCaseCd))
			{
				var childCaseCd = item.ChildCaseCD ?? string.Empty;
				if (ht.Contains(childCaseCd)) continue;

				ht.Add(childCaseCd, item);
                var relCase = SelectCase(childCaseCd);
				if (relCase == null)
					continue;

              /*  PXUIFieldAttribute.SetEnabled<CRCaseRelated.status>(CaseRelated.Cache, relCase, false);
                PXUIFieldAttribute.SetEnabled<CRCaseRelated.ownerID>(CaseRelated.Cache, relCase, false);
                PXUIFieldAttribute.SetEnabled<CRCaseRelated.workgroupID>(CaseRelated.Cache, relCase, false);*/

                yield return new PXResult<CRCaseReference, CRCaseRelated>(item, relCase);
			}

			var cache = CaseRefs.Cache;
			var oldIsDirty = cache.IsDirty;

			foreach (CRCaseReference item in 
				PXSelect<CRCaseReference,
					Where<CRCaseReference.childCaseCD, Equal<Required<CRCaseReference.childCaseCD>>>>.
				Select(this, currentCaseCd))
			{
				var parentCaseCd = item.ParentCaseCD ?? string.Empty;
				if (ht.Contains(parentCaseCd)) continue;
				var relCase = SelectCase(parentCaseCd);
				if(relCase == null)
					continue;

				ht.Add(parentCaseCd, item);
				cache.Delete(item);
				var newItem = (CRCaseReference)cache.CreateInstance();
				newItem.ParentCaseCD = currentCaseCd;
				newItem.ChildCaseCD = parentCaseCd;

			    switch (item.RelationType)
			    {
                    case CaseRelationTypeAttribute._DEPENDS_ON_VALUE:
			            newItem.RelationType = CaseRelationTypeAttribute._BLOCKS_VALUE;
                        break;
                    case CaseRelationTypeAttribute._DUBLICATE_OF_VALUE:
			            newItem.RelationType = CaseRelationTypeAttribute._DUBLICATE_OF_VALUE;
                        break;
                    case CaseRelationTypeAttribute._RELATED_VALUE:
			            newItem.RelationType = CaseRelationTypeAttribute._RELATED_VALUE;
                        break;
                    default:
			            newItem.RelationType = CaseRelationTypeAttribute._DEPENDS_ON_VALUE;
			            break;
			    }

				newItem = (CRCaseReference)cache.Insert(newItem);
				cache.IsDirty = oldIsDirty;
                yield return new PXResult<CRCaseReference, CRCaseRelated>(newItem, relCase);
			}
		}

I think it could get tricky, but you can give it a shot. Hope that helps and good luck.!