ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Core.Data Namespace / Version Class / Reconcile Method / Reconcile(ReconcileOptions,PostOptions) Method
If ReconcileOptions.TargetVersion is not specified in reconcileOptions, then the target version is the Default version.
If PostOptions.TargetVersion is not specified in postOptions, then the target version is the Default version.
Example Version

Reconcile(ReconcileOptions,PostOptions) Method
Reconciles and posts this version against a target version specified in reconcileOptions and postOptions. This method must be called on the MCT. Use QueuedTask.Run.
Syntax

Parameters

reconcileOptions
If ReconcileOptions.TargetVersion is not specified in reconcileOptions, then the target version is the Default version.
postOptions
If PostOptions.TargetVersion is not specified in postOptions, then the target version is the Default version.

Return Value

An instance of ReconcileResult indicating the results of the operation.
Exceptions
ExceptionDescription
reconcileOptions and/or postOptions is null.

This operation is not supported in client-server mode because the data store supports multi-branch versioning.

-or-

Multi-branch versioning does not support a ConflictResolutionType that favors the target version.

A Selection object specified in PartialPostSelections is not from a feature service feature class.

-or-

Reconcile cannot be performed in an active edit session.

A geodatabase-related exception has occurred.
This method or property must be called within the lambda passed to QueuedTask.Run
Remarks
If the underlying data store supports branch versioning and partial posting, this operation will post the data specified by PartialPostSelections to the Default version. In addition, after the partial posting operation is complete, the API will perform another Reconcile operation. This action may subsequently cause ReconcileResult.HasConflicts to be true.
Example
Illustrate version conflict information from a reconcile operation
public void GetVersionConflictsInfoInUpdateDeleteType(ServiceConnectionProperties featureServiceConnectionProperties, string featureClassName)
{
    // To illustrate the conflict between versions,
    // the feature is updated in the child version and deleted in the parent version.

    long featureObjectIDForEdit = Int64.MinValue;

    // Get branch versioned service
    using (Geodatabase fsGeodatabase = new Geodatabase(featureServiceConnectionProperties))
    using (VersionManager versionManager = fsGeodatabase.GetVersionManager())
    using (Version defaultVersion = versionManager.GetDefaultVersion())
    using (Geodatabase defaultGeodatabase = defaultVersion.Connect())
    using (FeatureClass defaultFeatureClass = defaultGeodatabase.OpenDataset<FeatureClass>(featureClassName))
    using (FeatureClassDefinition defaultFeatureClassDefinition = defaultFeatureClass.GetDefinition())
    {
        // Create a feature in the default version to edit in a branch
        defaultGeodatabase.ApplyEdits(() =>
        {
            using (RowBuffer rowBuffer = defaultFeatureClass.CreateRowBuffer())
            {
                rowBuffer["NAME"] = "Loblolly Pine";
                rowBuffer["TREEAGE"] = 1;
                rowBuffer[defaultFeatureClassDefinition.GetShapeField()] = new MapPointBuilderEx(new Coordinate2D(1, 1),
          SpatialReferenceBuilder.CreateSpatialReference(4152, 0)).ToGeometry();

                using (Feature feature = defaultFeatureClass.CreateRow(rowBuffer))
                {
                    featureObjectIDForEdit = feature.GetObjectID();
                }
            }
        });

        // Add newly created feature in the filter
        QueryFilter queryFilter = new QueryFilter { ObjectIDs = new List<long> { featureObjectIDForEdit } };

        // Create a branch version
        VersionDescription versionDescription = new VersionDescription("UpdateDeleteConflictType",
          "Update-Delete version conflict type", VersionAccessType.Private);

        // Edit the feature in the branch 
        using (Version editVersion = versionManager.CreateVersion(versionDescription))
        using (Geodatabase branchGeodatabase = editVersion.Connect())
        using (FeatureClass featureClass = branchGeodatabase.OpenDataset<FeatureClass>(featureClassName))
        using (RowCursor rowCursor = featureClass.Search(queryFilter, false))
        {
            branchGeodatabase.ApplyEdits(() =>
            {
                while (rowCursor.MoveNext())
                {
                    using (Row row = rowCursor.Current)
                    {
                        row["TREEAGE"] = 100;
                        row["NAME"] = $"{row["Name"]}_EditInBranch";
                        row.Store();
                    }
                }
            });

            // Delete the feature from the default version
            defaultFeatureClass.DeleteRows(queryFilter);

            // Reconcile options
            ReconcileOptions reconcileOptions = new ReconcileOptions(defaultVersion)
            {
                ConflictResolutionType = ConflictResolutionType.FavorEditVersion,
                ConflictDetectionType = ConflictDetectionType.ByRow,
                ConflictResolutionMethod = ConflictResolutionMethod.Continue
            };

            // Reconcile with default
            ReconcileResult reconcileResult = editVersion.Reconcile(reconcileOptions);

            // Check for conflicts
            bool hasConflictsReconcileResults = reconcileResult.HasConflicts;
            bool hasConflictsAfterReconcile = editVersion.HasConflicts();

            // Fetch conflicts
            IReadOnlyList<Conflict> conflictsAfterReconcile = editVersion.GetConflicts();

            // Iterate conflicts
            foreach (Conflict conflict in conflictsAfterReconcile)
            {
                // Object ID of row where conflict occurs
                long objectId = conflict.ObjectID;

                ConflictType conflictType = conflict.ConflictType;

                IReadOnlyList<FieldValue> ancestorVersionValues = conflict.AncestorVersionValues;
                object nameAncestor = ancestorVersionValues.FirstOrDefault(f => f.FieldName.Contains("NAME")).Value;
                object treeAgeAncestor = ancestorVersionValues.FirstOrDefault(f => f.FieldName.Contains("TREEAGE")).Value;

                IReadOnlyList<FieldValue> childVersionValues = conflict.ChildVersionValues;
                object nameChild = childVersionValues.FirstOrDefault(f => f.FieldName.Contains("NAME")).Value;
                object treeAgeChild = childVersionValues.FirstOrDefault(f => f.FieldName.Contains("TREEAGE")).Value;

                IReadOnlyList<FieldValue> parentVersionValues = conflict.ParentVersionValues;

                IReadOnlyList<Field> originalFields = defaultFeatureClassDefinition.GetFields();

                string datasetName = conflict.DatasetName;
            }
        }
    }
}
Reconciling and Posting a Version with its Parent in the same edit session
public void ReconcileAndPost2(Geodatabase geodatabase)
{
    // Get a reference to our version and our parent
    if (geodatabase.IsVersioningSupported())
    {
        using (VersionManager versionManager = geodatabase.GetVersionManager())
        using (Version currentVersion = versionManager.GetCurrentVersion())
        using (Version parentVersion = currentVersion.GetParent())
        {

            //// Create a ReconcileDescription object
            //At 2.x - 
            //ReconcileDescription reconcileDescription = new ReconcileDescription(parentVersion);
            //reconcileDescription.ConflictResolutionMethod = ConflictResolutionMethod.Continue; // continue if conflicts are found
            //reconcileDescription.WithPost = true;

            //// Reconcile and post
            //ReconcileResult reconcileResult = currentVersion.Reconcile(reconcileDescription);

            // ReconcileResult.HasConflicts can be checked as-needed

            // Create a ReconcileOptions object
            ReconcileOptions reconcileOptions = new ReconcileOptions(parentVersion);
            reconcileOptions.ConflictResolutionMethod = ConflictResolutionMethod.Continue; // continue if conflicts are found
            reconcileOptions.ConflictDetectionType = ConflictDetectionType.ByRow; //Default
            reconcileOptions.ConflictResolutionType = ConflictResolutionType.FavorTargetVersion;//or FavorEditVersion

            PostOptions postOptions = new PostOptions(parentVersion);
            //var postOptions = new PostOptions(); for default version
            postOptions.ServiceSynchronizationType = ServiceSynchronizationType.Synchronous;//Default

            // Reconcile
            ReconcileResult reconcileResult = currentVersion.Reconcile(reconcileOptions, postOptions);
            if (reconcileResult.HasConflicts)
            {
                //TODO resolve conflicts

            }

        }
    }
}
Partial Posting
// Partial posting allows developers to post a subset of changes made in a version.
// One sample use case is an electric utility that uses a version to design the facilities in
// a new housing subdivision. At some point in the process, one block of new houses have been
// completed, while the rest of the subdivision remains unbuilt.  Partial posting allows the user
// to post the completed work, while leaving not yet constructed features in the version to be
// posted later. Partial posting requires a branch-versioned feature service using ArcGIS
// Enterprise 10.9 and higher

// Specify a set of features that were constructed
QueryFilter constructedFilter = new QueryFilter()
{
    WhereClause = "ConstructedStatus = 'True'"
};
// This selection represents the inserts and updates to the support
// structure feature class that we wish to post
using (Selection constructedSupportStructures = supportStructureFeatureClass.Select(constructedFilter, SelectionType.ObjectID, SelectionOption.Normal))
{
    // Specifying which feature deletions you wish to post is slightly trickier, since you cannot issue
    // a query to fetch a set of deleted features Instead, a list of ObjectIDs must be used
    using (Selection deletedSupportStructures = supportStructureFeatureClass.Select(
                                        null, SelectionType.ObjectID, SelectionOption.Empty))
    {
        deletedSupportStructures.Add(deletedSupportStructureObjectIDs);  //deletedSupportStructureObjectIDs is
                                                                         //defined as List<long>

        //Perform the reconcile with partial post
        //At 2.x - 
        //ReconcileDescription reconcileDescription = new ReconcileDescription();
        //reconcileDescription.ConflictDetectionType = ConflictDetectionType.ByColumn;
        //reconcileDescription.ConflictResolutionMethod = ConflictResolutionMethod.Continue;
        //reconcileDescription.ConflictResolutionType = ConflictResolutionType.FavorEditVersion;
        //reconcileDescription.PartialPostSelections = new List<Selection>() { constructedSupportStructures, deletedSupportStructures };
        //reconcileDescription.WithPost = true;

        //ReconcileResult reconcileResult = designVersion.Reconcile(reconcileDescription);

        ReconcileOptions reconcileOptions = new ReconcileOptions();//reconcile against Default
        reconcileOptions.ConflictDetectionType = ConflictDetectionType.ByColumn;
        reconcileOptions.ConflictResolutionMethod = ConflictResolutionMethod.Continue;
        reconcileOptions.ConflictResolutionType = ConflictResolutionType.FavorEditVersion;

        PostOptions postOptions = new PostOptions();//post against Default
        postOptions.PartialPostSelections = new List<Selection>() {
              constructedSupportStructures, deletedSupportStructures };
        postOptions.ServiceSynchronizationType = ServiceSynchronizationType.Synchronous;

        ReconcileResult reconcileResult = designVersion.Reconcile(reconcileOptions, postOptions);

        //TODO process result(s)
    }
}
Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3 or higher.
See Also