Question

我有一个固定大小（10）的类型int数组，它没有完全填满。

我想计算数组中有多少个整数，这样我就知道如果我想在数组中添加一个整数，那么将数组索引到什么值。（这样我就不会替换另一个值）

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="testMultipleDDLpopulate.aspx.cs" Inherits="ABCFieldTicketWebApp.testMultipleDDLpopulate" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:DropDownList ID="ddlRigYard" runat="server" DataTextField="EquipNumber" DataValueField="EquipNumber" AutoPostback="True" OnSelectedIndexChanged="ddlRigYard_SelectedIndexChanged" Height="16px" Width="196px"></asp:DropDownList>
        <asp:SqlDataSource ID="dsRigYard" runat="server" ConnectionString="<%$ ConnectionStrings:LESFieldTicketConnectionString %>" SelectCommand="SELECT [EquipNumber], [LocationMovedTo], [NAVLocationCode], [NAVLocal2] FROM [VW_LES_EquipCurrentLocation]"></asp:SqlDataSource>
        <asp:TextBox ID="txtLocationMovedTo" runat="server"></asp:TextBox>
        <asp:TextBox ID="txtNAVLocationCode" runat="server"></asp:TextBox>
        <asp:TextBox ID="txtNAVLocal2" runat="server"></asp:TextBox>
    </div>
    <div>
        <asp:DropDownList ID="ddlResourceCode" runat="server" DataTextField="[Name]" DataValueField="[No_]" AutoPostback="True" OnSelectedIndexChanged="ddlResourceCode_SelectedIndexChanged" Height="16px" Width="196px"></asp:DropDownList>
        <asp:SqlDataSource ID="dsResourceCode" runat="server" ConnectionString="<%$ ConnectionStrings:LESFieldTicketConnectionString %>" SelectCommand="SELECT [Name], [No_], [Unit Price] AS Unit_Price, [Base Unit Of Measure] AS Base_Unit_Of_Measure, [Resource Group No_] AS Resource_Group_No_, [LOB], [MajorAcct] FROM [VW_LES_NAVResourceCode]"></asp:SqlDataSource>
        <asp:TextBox ID="txtNo" runat="server"></asp:TextBox>
        <asp:TextBox ID="txtUnitPrice" runat="server"></asp:TextBox>
        <asp:TextBox ID="txtUOM" runat="server"></asp:TextBox>
        <asp:TextBox ID="txtResourceGrp" runat="server"></asp:TextBox>
        <asp:TextBox ID="txtLOB" runat="server"></asp:TextBox>
        <asp:TextBox ID="txtMajorAcct" runat="server"></asp:TextBox>
    </div>
    </form>
</body>
</html>


using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;

namespace ABCFieldTicketWebApp
{
    public partial class testMultipleDDLpopulate : System.Web.UI.Page
    {
        protected void Page_Load1(object sender, EventArgs e)
        {
            if (!this.IsPostBack)
            {
                this.PopulateDropDownList1();
            }
        }
        protected void Page_Load2(object sender, EventArgs e)
        {
            if (!this.IsPostBack)
            {
                this.PopulateDropDownList2();
            }
        }
        private void PopulateDropDownList1()
        {
            string constr1 = ConfigurationManager.ConnectionStrings["LESFieldTicketConnectionString"].ConnectionString;
            using (SqlConnection con1 = new SqlConnection(constr1))
            {
                using (SqlCommand cmd1 = new SqlCommand("SELECT EquipNumber FROM VW_LES_EquipCurrentLocation", con1))
                {
                    using (SqlDataAdapter da1 = new SqlDataAdapter(cmd1))
                    {
                        con1.Open();
                        DataSet ds1 = new DataSet();
                        da1.Fill(ds1);
                        this.ddlRigYard.DataTextField = "EquipNumber";
                        this.ddlRigYard.DataValueField = "EquipNumber";
                        this.ddlRigYard.DataSource = ds1;
                        this.ddlRigYard.DataBind();
                        this.ddlRigYard.Items.Insert(0, new System.Web.UI.WebControls.ListItem("Please Select", "0"));
                    }
                }
            }
        }
        protected void ddlRigYard_SelectedIndexChanged(object sender, EventArgs e)
        {
            string selected = ddlRigYard.SelectedItem.Value;

            string constr1 = ConfigurationManager.ConnectionStrings["LESFieldTicketConnectionString"].ConnectionString;
            using (SqlConnection con1 = new SqlConnection(constr1))
            {

                SqlCommand command1 = new SqlCommand("SELECT [EquipNumber], [LocationMovedTo], [NAVLocationCode], [NAVLocal2] FROM [VW_LES_EquipCurrentLocation] WHERE EquipNumber= @EquipNumber", con1);
                command1.Parameters.AddWithValue("@EquipNumber", selected);
                command1.CommandType = CommandType.Text;
                con1.Open();
                SqlDataReader reader = command1.ExecuteReader();
                using (reader)
                {
                    if (reader.HasRows)
                    {
                        reader.Read();

                        //add as many as needed to fill your textboxes
                        txtLocationMovedTo.Text = reader.GetString(1);
                        txtNAVLocationCode.Text = reader.GetString(2);
                        txtNAVLocal2.Text = reader.GetString(3);
                    }
                    else { }
                }
            }
        }
        private void PopulateDropDownList2()
        {
            string constr2 = ConfigurationManager.ConnectionStrings["LESFieldTicketConnectionString"].ConnectionString;
            using (SqlConnection con2 = new SqlConnection(constr2))
            {
                using (SqlCommand cmd2 = new SqlCommand("SELECT [Name], [No_] FROM [VW_LES_NAVResourceCode]", con2))
                {
                    using (SqlDataAdapter da2 = new SqlDataAdapter(cmd2))
                    {
                        con2.Open();
                        DataSet ds2 = new DataSet();
                        da2.Fill(ds2);
                        this.ddlRigYard.DataTextField = "[Name]";
                        this.ddlRigYard.DataValueField = "[No_]";
                        this.ddlRigYard.DataSource = ds2;
                        this.ddlRigYard.DataBind();
                        this.ddlRigYard.Items.Insert(0, new System.Web.UI.WebControls.ListItem("Please Select", "0"));
                    }
                }
            }
        }
        protected void ddlResourceCode_SelectedIndexChanged(object sender, EventArgs e)
        {
            string selected = ddlResourceCode.SelectedItem.Value;

            string constr2 = ConfigurationManager.ConnectionStrings["LESFieldTicketConnectionString"].ConnectionString;
            using (SqlConnection con2 = new SqlConnection(constr2))
            {

                SqlCommand command2 = new SqlCommand("SELECT [Name], [No_], [Unit Price] AS Unit_Price, [Base Unit Of Measure] AS Base_Unit_Of_Measure, [Resource Group No_] AS Resource_Group_No_, [LOB], [MajorAcct] FROM [VW_LES_NAVResourceCode] WHERE [No_]=@[No_]", con2);
                command2.Parameters.AddWithValue("@[No_]", selected);
                command2.CommandType = CommandType.Text;
                con2.Open();
                SqlDataReader reader = command2.ExecuteReader();
                using (reader)
                {
                    if (reader.HasRows)
                    {
                        reader.Read();

                        //add as many as needed to fill your textboxes
                        txtNo.Text = reader.GetString(1);
                        txtUnitPrice.Text = reader.GetString(2);
                        txtUOM.Text = reader.GetString(3);
                        txtResourceGrp.Text = reader.GetString(4);
                        txtLOB.Text = reader.GetString(5);
                        txtMajorAcct.Text = reader.GetString(6);
                    }
                    else { }
                }
            }
        }
    }
}

当我输出变量计数器时，我得到值“0”。

我查看了几个Stack Overflow帖子，我似乎找到了一些可以帮助我找到解决方案的东西！任何帮助或建议都会有很大的帮助。

感谢。

修改我能够得到我的问题的答案，但我后悔发帖因为我现在有2个声望点！你们这些人很苛刻！这是正确的答案

//Define Array
int counter=0;
int scores[10] = {92,87,94,99,96};

//Count how many elements are in the score array
for (int i = 0; i < 10; i++)
{
    if (scores[i] == 1)
    {
        counter++;
    }
}

Answer 1

例如，您可以认为包含0（或-1）的数组元素是未填充的元素。

在任何情况下，数组的每个元素都应包含实际值或0。

此初始化

int scores[10] = {92,87,94,99,96};

相当于

int scores[10] = {92,87,94,99,96,0,0,0,0,0};

所以循环看起来像

for ( size_t i = 0; i < sizeof( scores ) / sizeof( *scores ); i++ )
{
    if ( scores[i] != 0)
    {
        counter++;
    }
}

如果要对非填充元素使用值-1，则必须显式初始化非填充元素，例如

int scores[10] = {92,87,94,99,96,-1,-1,-1,-1,-1};

并且循环看起来像

for ( size_t i = 0; i < sizeof( scores ) / sizeof( *scores ); i++ )
{
    if ( scores[i] != -1)
    {
        counter++;
    }
}

Answer 2

你不必做所有这些。每次在数组中存储数字时，只需递增计数器，计数器本身就会告诉您需要存储下一个数字的索引。

Answer 3

使用std::vector，然后使用size方法：

std::vector v={1,2,4,8};
cout << "Vector size is: " << v.size() << "\n"

如何计算未完全填充的数组中的整数

3 个答案: