C#判断语句中数据类型

在用C#学习写一个最简单的图书借阅管理系统，想要实现输入一本书的数量后，如果数量大于0，“借阅状态”能判断为“可借阅”，反之则不可借阅，但是Qty用String类型无法用>来判断，改成int也报错，求问怎么改

public class Book
{
    public string BookName { get; set; }
    public string BookAuthor { get; set; }
    public string BookQty { get; set; }
    public string BookLoc { get; set; }
    public string BookStatus { get; set; }

}
public class Library
{
    List<Book> Books = new List<Book>();
    List<Book> books = new List<Book>();
    
    #region 录入
    public void exe0()
    {

        int i = 1;
        string str = "";
        while (str != "ok")
        {
            Console.WriteLine("请输入第{0}本书的书名：", i);
            string name = Console.ReadLine();
            Console.WriteLine("请输入第{0}本书的作者：", i);
            string author = Console.ReadLine();
            Console.WriteLine("请输入第{0}本书的数量：", i);
            string qty = Console.ReadLine();
            Console.WriteLine("请输入第{0}本书的位置：", i);
            string loc = Console.ReadLine();
            if (qty > 0)
            {
                string status = "可借阅";
            }
            else 
            {
                string status = "不可借阅";
            }

            Books.Add(new Book { BookName = name, BookAuthor = author, BookQty = qty, BookLoc = loc, BookStatus = status});
            i = i + 1;
            Console.WriteLine("输入 ok 停止录入，按任意键继续");
            str = Console.ReadLine();

        }
        Console.WriteLine("");
        Console.WriteLine("");
        Console.WriteLine("书名\t作者\t数量\t位置\t借阅状态");
        foreach (var item in Books)
        {
            Console.WriteLine("{0}\t{1}\t{2}\t{3}\t{4}", item.BookName, item.BookAuthor, item.BookQty, item.BookLoc, item.BookStatus);
        }

    }

运行报错
Operator '>' cannot be applied to operands of type 'string' and 'int'
The name 'status' does not exist in the current context

直接转int型啊，int qty= int.Parse(console.ReadLine());//当然最好加上try catch 处理输入非数字的异常

错误原因：不能拿string 和int进行比较。我帮你把代码改好了。直接运行即可

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Decorator_Test
{
    public class Book
    {
        public string BookName { get; set; }
        public string BookAuthor { get; set; }
        public string BookQty { get; set; }
        public string BookLoc { get; set; }
        public string BookStatus { get; set; }

    }
    public class Library
    {
        List<Book> Books = new List<Book>();
        List<Book> books = new List<Book>();

        #region 录入
        public void exe0()
        {

            int i = 1;
            string str = "";
            while (str != "ok")
            {
                Console.WriteLine("请输入第{0}本书的书名：", i);
                string name = Console.ReadLine();
                Console.WriteLine("请输入第{0}本书的作者：", i);
                string author = Console.ReadLine();
                Console.WriteLine("请输入第{0}本书的数量：", i);
                string qty = Console.ReadLine();
                Console.WriteLine("请输入第{0}本书的位置：", i);
                string loc = Console.ReadLine();
                int count;
                string status;
                if (Int32.TryParse(qty, out count) && count > 0)
                {
                    status = "可借阅";
                }
                else
                {
                    status = "不可借阅";
                }

                Books.Add(new Book { BookName = name, BookAuthor = author, BookQty = qty, BookLoc = loc, BookStatus = status });
                i = i + 1;
                Console.WriteLine("输入 ok 停止录入，按任意键继续");
                str = Console.ReadLine();

            }
            Console.WriteLine("");
            Console.WriteLine("");
            Console.WriteLine("书名\t作者\t数量\t位置\t借阅状态");
            foreach (var item in Books)
            {
                Console.WriteLine("{0}\t{1}\t{2}\t{3}\t{4}", item.BookName, item.BookAuthor, item.BookQty, item.BookLoc, item.BookStatus);
            }

        }
        #endregion
    }
    class Program
    {
        static void Main(string[] args)
        {
            Library library = new Library();
            library.exe0();
        }
    }
}

```c#

```