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copied!<p>I just created a <code>generic filter function</code> using <code>ExpressionTree</code> .. I want to <code>share</code> with you guys... </p> <p><code>Start</code></p> <pre><code>var allFiltered= Filter(AllCustomer, "Name", "Moumit"); public static List<T> Filter<T>(this List<T> Filterable, string PropertyName, object ParameterValue) { ConstantExpression c = Expression.Constant(ParameterValue); ParameterExpression p = Expression.Parameter(typeof(T), "xx"); MemberExpression m = Expression.PropertyOrField(p, PropertyName); var Lambda = Expression.Lambda<Func<T, Boolean>>(Expression.Equal(c, m), new[] { p }); Func<T, Boolean> func = Lambda.Compile(); return Filterable.Where(func).ToList(); } </code></pre> <p><code>One More</code></p> <pre><code>string singlePropertyName=GetPropertyName((Property.Customer p) => p.Name); public static string GetPropertyName<T, U>(Expression<Func<T, U>> expression) { MemberExpression body = expression.Body as MemberExpression; // if expression is not a member expression if (body == null) { UnaryExpression ubody = (UnaryExpression)expression.Body; body = ubody.Operand as MemberExpression; } return string.Join(".", body.ToString().Split('.').Skip(1)); } </code></pre> <p><code>Make it more expandable</code></p> <pre><code>string multiCommaSeparatedPropertyNames=GetMultiplePropertyName<Property.Customer>(c => c.CustomerId, c => c.AuthorizationStatus) public static string GetMultiplePropertyName<T>(params Expression<Func<T, object>>[] expressions) { string[] propertyNames = new string[expressions.Count()]; for (int i = 0; i < propertyNames.Length; i++) { propertyNames[i] = GetPropertyName(expressions[i]); } return propertyNames.Join(); } </code></pre> <p>....... I know it also can be done using <code>Reflection</code> ... but this one is tremendous fast or i can say equivalent to <code>Lambda</code> after first compilation ... The very first iteration is just an average 10 millisecond slow... So this is <code>Expression Tree</code> magic. Simple and fantastic....I think ...!!!!!!!!</p>

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