// ** Create a string attribute ** StringAttributeMetadata stringAttribute = new StringAttributeMetadata { // Set base properties SchemaName = "new_string", DisplayName = new Label("Sample String", 1033), RequiredLevel = new AttributeRequiredLevelManagedProperty(AttributeRequiredLevel.None), Description = new Label("String Attribute", 1033), // Set extended properties MaxLength = 100 }; // Create the request. CreateAttributeRequest createAttributeRequest = new CreateAttributeRequest { EntityName = "EntityLogicalName", Attribute = stringAttribute }; // Execute the request. Get Response CreateAttributeResponse resp = (CreateAttributeResponse)_service.Execute(createAttributeRequest);