基于Combobox值构建动态LINQ查询

using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;

namespace DynamicLinqQuery
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            comboBox1.SelectedIndexChanged += ComboBox1_SelectedIndexChanged;
        }

        private void ComboBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            var selectedValue = comboBox1.SelectedItem.ToString();
            var query = BuildDynamicLinqQuery(selectedValue);
            var result = query.ToList();
        }

        private IQueryable<string> BuildDynamicLinqQuery(string selectedValue)
        {
            var data = new List<string> { "Apple", "Banana", "Orange", "Pineapple", "Grape" };
            var query = data.AsQueryable();

            if (selectedValue == "StartsWithA")
            {
                query = query.Where(x => x.StartsWith("A"));
            }
            else if (selectedValue == "ContainsE")
            {
                query = query.Where(x => x.Contains("E"));
            }
            else if (selectedValue == "LongerThan5")
            {
                query = query.Where(x => x.Length > 5);
            }

            return query;
        }
    }
}