const 编译时常量
static readonly 运行时常量
直接上代码
1.新建一个类库BLL->添加类Teacher
1 using System;
2 using System.Collections.Generic;
3 using System.Linq;
4 using System.Text;
5 using System.Threading.Tasks;
6
7 namespace BLL
8 {
9 public class Teacher
10 {
11 public static readonly int i = 3;
12 public static readonly string j = "static";
13
14 public const int m = 6;
15 public const string n = "const";
16 }
17 }
2.新建空Web应用程序->添加Webform
/*页面HTML*/
1 <html xmlns="http://www.w3.org/1999/xhtml"> 2 <head runat="server"> 3 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> 4 <title></title> 5 </head> 6 <body> 7 <form id="form1" runat="server"> 8 <div> 9 <asp:TextBox ID="txti" runat="server"></asp:TextBox> 10 <asp:TextBox ID="txtj" runat="server"></asp:TextBox> 11 <asp:TextBox ID="txtm" runat="server"></asp:TextBox> 12 <asp:TextBox ID="txtn" runat="server"></asp:TextBox> 13 </div> 14 </form> 15 </body> 16 </html>
/*后台代码*/
1 namespace WebApplication1
2 {
3 public partial class WebForm1 : System.Web.UI.Page
4 {
5 protected void Page_Load(object sender, EventArgs e)
6 {
7 Teacher t = new Teacher();
8 this.txti.Text=Teacher.i.ToString();
9 this.txtj.Text=Teacher.j.ToString();
10 this.txtm.Text = Teacher.m.ToString();
11 this.txtn.Text = Teacher.n.ToString();
12 }
13 }
14 }
3.在IIS发布访问后(页面显示)
4.修改Teacher类中常量值
namespace BLL
{
public class Teacher
{
public static readonly int i = 5;
public static readonly string j = "static_modify";
public const int m = 9;
public const string n = "const_modify";
}
}
5.生成解决方案,替换发布包中的BLL.dll后访问页面结果发现
static变量修改成功了,而const变量修改失败...
结论 :const 会将值便已在代码中,而static只是保留了引用
时间： 2024-08-03 19:30:53