016 - DataGridTagHelper.cs

using System.ComponentModel;
using System.Reflection;
using Microsoft.AspNetCore.Razor.TagHelpers;

namespace TagHelperSample.TagHelpers;
public class DataGridTagHelper : TagHelper
{
    [HtmlAttributeName("Items")]
    public IEnumerable<object> Items { get; set; }

    public override void Process(
        TagHelperContext context,
        TagHelperOutput output)
    {
        output.TagName = "table";
        output.Attributes.Add("class", "table");
        var props = GetItemProperties();

        TableHeader(output, props);
        TableBody(output, props);
    }

    private PropertyInfo[] GetItemProperties()
    {
        var listType = Items.GetType();
        Type itemType;
        if (listType.IsGenericType)
        {
            itemType = listType.GetGenericArguments()
                .First();
            return itemType.GetProperties(
                BindingFlags.Public |
                BindingFlags.Instance);
        }
        return new PropertyInfo[] { };
    }

    private void TableHeader(
        TagHelperOutput output,
        PropertyInfo[] props)
    {
        output.Content.AppendHtml("<thead>");
        output.Content.AppendHtml("<tr>");
        foreach (var prop in props)
        {
            var name = GetPropertyName(prop);
            output.Content.AppendHtml($"<th>{name}</th>");
        }
        output.Content.AppendHtml("</tr>");
        output.Content.AppendHtml("</thead>");
    }

    private string GetPropertyName(
        PropertyInfo property)
    {
        var attribute = property
            .GetCustomAttribute<DisplayNameAttribute>();
        if (attribute != null)
        {
            return attribute.DisplayName;
        }
        return property.Name;
    }

    private void TableBody(
        TagHelperOutput output,
        PropertyInfo[] props)
    {
        output.Content.AppendHtml("<tbody>");
        foreach (var item in Items)
        {
            output.Content.AppendHtml("<tr>");
            foreach (var prop in props)
            {
                var value = GetPropertyValue(prop, item);
                output.Content.AppendHtml(
                    $"<td>{value}</td>");
            }
            output.Content.AppendHtml("</tr>");
        }
        output.Content.AppendHtml("</tbody>");
    }
    private object GetPropertyValue(
        PropertyInfo property,
        object instance)
    {
        return property.GetValue(instance);
    }

}