Get scaffolder to generate fields in specific order

问题

I am trying to get asp.net core MVC to scaffold a Razor View with fields in a different order than the apparently default alphabetical order. I've got a simple model:

public class Application : EntityBase
{
    [Display(Name = "Naam", Order = 1)]
    public string Name { get; set; }

    [Display(Name = "Omschrijving", Order = 2)]
    public string Description { get; set; }
}

I want the scaffolder to generate a field for Name before Description. How to do this?

I've been trying to come up with a solution in the Razor template. The relevant code is:

...
IEnumerable<PropertyMetadata> properties = Model.ModelMetadata.Properties;
foreach (var property in properties)
{
    if (property.Scaffold && !property.IsPrimaryKey && !property.IsForeignKey)
    {
...

I was hoping that a property had an Order-property, so I could write something like

foreach (var property in properties.OrderBy(p => p.Order))

Any ideas?

回答1:

So, after some (deep) digging I came up with a solution. As I allready customized the templates, it was acceptable to add yet another customization. I ended up creating a helper class ScaffoldHelpers.cs:

public class ScaffoldHelpers
{
    public static IEnumerable<PropertyMetadata> GetPropertiesInDisplayOrder(string typename, IEnumerable<PropertyMetadata> properties)
    {
        Type type = Type.GetType($"{typename}, {typename.Split('.')[0]}");
        SortedList<string, PropertyMetadata> propertiesList = new SortedList<string, PropertyMetadata>();
        foreach (PropertyMetadata property in properties)
        {
            int order = 0;
            if (type != null)
            {
                var member = type.GetMember(property.PropertyName)[0];
                var displayAttribute = member.GetCustomAttribute<System.ComponentModel.DataAnnotations.DisplayAttribute>();
                if (displayAttribute != null)
                {
                    order = displayAttribute.Order;
                }
            }
            propertiesList.Add($"{order:000} - {property.PropertyName}", property);
        }
        return propertiesList.Values.AsEnumerable();
    }

}

This iterates over all the properties, and determines if a [Display()] attribute is specified. If so, it gets the value of the Order-parameter. If you don't specify this, the Order-property will be zero. Using a SortedList and making sure the key is ordered by the specified order, I'm able to easily return an IEnumerable<PropertyMetadata> in the desired order.

In the template, I needed to add @using for this helper-class. After that, I could insert the following into the template:

...
IEnumerable<PropertyMetadata> properties = Model.ModelMetadata.Properties;

// added:
properties = ScaffoldHelpers.GetPropertiesInDisplayOrder(Model.ViewDataTypeName, properties);

foreach (var property in properties)
{
    if (property.Scaffold && !property.IsPrimaryKey && !property.IsForeignKey)
    {
...

That's it!

来源：https://stackoverflow.com/questions/40530823/get-scaffolder-to-generate-fields-in-specific-order