如何在switch语句中声明由groupby生成的IQueryable变量

var data = new List<Student>
{
    new Student { Name = "Alice", Grade = "A" },
    new Student { Name = "Bob", Grade = "B" },
    new Student { Name = "Alice", Grade = "B" },
    new Student { Name = "Bob", Grade = "A" }
};

// 使用LINQ查询表达式进行groupby操作
var query = from student in data
            group student by student.Name into studentGroup
            select studentGroup;

// 或者使用LINQ方法链进行groupby操作
var query = data.GroupBy(student => student.Name);

// 将结果赋值给一个IQueryable变量
IQueryable<IGrouping<string, Student>> groupedData = query.AsQueryable();

switch (condition)
{
    case "Alice":
        // 根据条件使用IQueryable变量进行筛选或操作
        var aliceData = groupedData.Where(group => group.Key == "Alice");
        // ...
        break;
    case "Bob":
        // 根据条件使用IQueryable变量进行筛选或操作
        var bobData = groupedData.Where(group => group.Key == "Bob");
        // ...
        break;
    default:
        // 处理其他情况
        // ...
        break;
}