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    <p>I didn't profile the following code, but it must be very performant on complex structures.</p> <p>1) Uses dynamic code generation.</p> <p>2) Uses type-based cache for generated dynamic delegates.</p> <pre><code>public class VisitorManager : HashSet&lt;object&gt; { delegate void Visitor(VisitorManager manager, object entity); Dictionary&lt;Type, Visitor&gt; _visitors = new Dictionary&lt;Type, Visitor&gt;(); void ConvertToUpperEnum(IEnumerable entity) { // TODO: this can be parallelized, but then we should thread-safe lock the cache foreach (var obj in entity) ConvertToUpper(obj); } public void ConvertToUpper(object entity) { if (entity != null &amp;&amp; !Contains(entity)) { Add(entity); var visitor = GetCachedVisitor(entity.GetType()); if (visitor != null) visitor(this, entity); } } Type _lastType; Visitor _lastVisitor; Visitor GetCachedVisitor(Type type) { if (type == _lastType) return _lastVisitor; _lastType = type; return _lastVisitor = GetVisitor(type); } Visitor GetVisitor(Type type) { Visitor result; if (!_visitors.TryGetValue(type, out result)) _visitors[type] = result = BuildVisitor(type); return result; } static MethodInfo _toUpper = typeof(string).GetMethod("ToUpper", new Type[0]); static MethodInfo _convertToUpper = typeof(VisitorManager).GetMethod("ConvertToUpper", BindingFlags.Instance | BindingFlags.Public); static MethodInfo _convertToUpperEnum = typeof(VisitorManager).GetMethod("ConvertToUpperEnum", BindingFlags.Instance | BindingFlags.NonPublic); Visitor BuildVisitor(Type type) { var visitorManager = Expression.Parameter(typeof(VisitorManager), "manager"); var entityParam = Expression.Parameter(typeof(object), "entity"); var entityVar = Expression.Variable(type, "e"); var cast = Expression.Assign(entityVar, Expression.Convert(entityParam, type)); // T e = (T)entity; var statements = new List&lt;Expression&gt;() { cast }; foreach (var prop in type.GetProperties()) { // if cannot read or cannot write - ignore property if (!prop.CanRead || !prop.CanWrite) continue; var propType = prop.PropertyType; // if property is value type - ignore property if (propType.IsValueType) continue; var isString = propType == typeof(string); // if string type but no password in property name - ignore property if (isString &amp;&amp; !prop.Name.Contains("password")) continue; #region e.Prop var propAccess = Expression.Property(entityVar, prop); // e.Prop #endregion #region T value = e.Prop var value = Expression.Variable(propType, "value"); var assignValue = Expression.Assign(value, propAccess); #endregion if (isString) { #region if (value != null) e.Prop = value.ToUpper(); var ifThen = Expression.IfThen(Expression.NotEqual(value, Expression.Constant(null, typeof(string))), Expression.Assign(propAccess, Expression.Call(value, _toUpper))); #endregion statements.Add(Expression.Block(new[] { value }, assignValue, ifThen)); } else { #region var i = value as IEnumerable; var enumerable = Expression.Variable(typeof(IEnumerable), "i"); var assignEnum = Expression.Assign(enumerable, Expression.TypeAs(value, enumerable.Type)); #endregion #region if (i != null) manager.ConvertToUpperEnum(i); else manager.ConvertToUpper(value); var ifThenElse = Expression.IfThenElse(Expression.NotEqual(enumerable, Expression.Constant(null)), Expression.Call(visitorManager, _convertToUpperEnum, enumerable), Expression.Call(visitorManager, _convertToUpper, value)); #endregion statements.Add(Expression.Block(new[] { value, enumerable }, assignValue, assignEnum, ifThenElse)); } } // no blocks if (statements.Count &lt;= 1) return null; return Expression.Lambda&lt;Visitor&gt;(Expression.Block(new[] { entityVar }, statements), visitorManager, entityParam).Compile(); } } </code></pre>
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    1. POHow to Optimize this method
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    1. USLex Lavnikov
    1. USLex Lavnikov
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      1. VTUpMod
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    1. COPlease note that `Expression.Assign` is new in .NET 4.0.
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      1. USSteven
 

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