如何计算列表长度 [英] How do I calculate length of list

问题描述

我试着计算一下列表的长度

它给了我一个错误

这是我的班级文件



我尝试过：

I tried to calculate length of list
It gives me an error
This is my class file

What I have tried:

Delete cfmdeletelist = new Delete();
       List<Delete> DeleteList = new List<Delete>();
       DeleteList = cfmdeletelist.getCurrentRow();
       for(int i = 0; i < cfmdeletelist.length; i++)

Severity	Code	Description	Project	File	Line	Suppression State
Error	CS1061	'Delete' does not contain a definition for 'length' and no extension method 'length' accepting a first argument of type 'Delete' could be found (are you missing a using directive or an assembly reference?)	eadd - Copy (2)	C:\Users\Tan\Desktop\eadd - Copy (2)\StaffHomeLoan.aspx.cs	163	Active

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Configuration;
using System.Data.SqlClient;
using System.Data;
using System.Text;

/// <summary>
/// Summary description for Delete
/// </summary>
public class Delete
{

    public int loanterm { get; set; }
    public String Type { get; set; }
    public int loanrate { get; set; }
    public List<Delete> getCurrentRow()
        {
        List<Delete> deletelist = new List<Delete>();

        // Step 4 :Retrieve connection string from web.config
        string DBConnect = ConfigurationManager.ConnectionStrings["ConnStr"].ConnectionString;


        // Step 5 :Create SQLcommand to select LoanTerm and LoanRate from LoanRate table where the rate is current

        StringBuilder sqlStr = new StringBuilder();
        sqlStr.AppendLine("SELECT  LoanRate,LoanTerm,Loanloantype From LoanMaster ");
 


        // Step 6 :Instantiate SqlConnection instance and SqlCommand instance

        SqlConnection myConn = new SqlConnection(DBConnect);
        SqlCommand cmd = new SqlCommand(sqlStr.ToString(), myConn);

        // Step 7 :Open connection then execute reader
        myConn.Open();
        SqlDataReader reader = cmd.ExecuteReader();

        // Step 8 : if reader has no rows return, set the typelist to null
        if (!reader.HasRows)
        {
            deletelist = null;
        }
        else
                 

            while (reader.Read())
            {
                Delete Deleted = new Delete();

                Deleted.Type = reader["Loanloantype"].ToString();
                Deleted.loanterm = Convert.ToInt32(reader["LoanTerm"]);
                Deleted.loanrate = Convert.ToInt32(reader["LoanRate"]);

               
               deletelist.Add(Deleted);
                List<Delete> distinct = deletelist.ToList();
            }
        // Step 11: Close the reader and connection 
        myConn.Close();
        reader.Close();
        return deletelist;
    }



}

    //
    // TODO: Add constructor logic here
    //
}

推荐答案

你试过吗

Have you tried

for(int i = 0; i < cfmdeletelist.Length; i++)

（资本L的长度）



您需要使用声明为List的变量 - > DeleteList

(Capital L in Length)

You need to use the variable declared as a List -> DeleteList

Delete elementToDelete;
for(int i = 0; i < DeleteList.Length; i++)
{
    elementToDelete = DeleteList[i];
    elementToDelete.Dispose(); // Or what ever you need to do
}

当你声明一个你自己类型的变量时这样

When you declare a variable of your own type like this

Delete cfmdeletelist = new Delete();

对象 cfmdeletelist 只包含方法您已定义的属性。

您是否为类定义了任何Length属性删除？

the object cfmdeletelist will only contain the methods and properties you have defined.
Did you define any Length property for the class Delete?

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