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C# 统计销售数量并在listview C中显示#_C#_Sql - Fatal编程技术网

C# 统计销售数量并在listview C中显示#

C# 统计销售数量并在listview C中显示#,c#,sql,C#,Sql,我有以下代码需要列出(在列表视图中)每个产品、产品类型和购买该产品的客户数量。我试过这个,但不起作用 我不确定是否需要创建另一个类,然后定义列表以及需要在ListViewItems中包含的内容。我不熟悉C#编码,但能够使用类似的方法显示数据,但以前没有人要求我做计算。任何帮助都将不胜感激。如果需要,我可以提供文件(项目和SQL) namespace Acme { public partial class frmMainForm : Form { public frmMainForm()

我有以下代码需要列出(在列表视图中)每个产品、产品类型和购买该产品的客户数量。我试过这个,但不起作用

我不确定是否需要创建另一个类,然后定义列表以及需要在ListViewItems中包含的内容。我不熟悉C#编码,但能够使用类似的方法显示数据,但以前没有人要求我做计算。任何帮助都将不胜感激。如果需要,我可以提供文件(项目和SQL)

namespace Acme
{
public partial class frmMainForm : Form
{
    public frmMainForm()
    {
        InitializeComponent();
    }
     //Not sure if the following is correct//   
    private void DisplaySales()
    {
        string selectQuery;

        selectQuery = "SELECT Products.ProductName, ProductTypes.ProductType, COUNT(Sales.ProductID) as SALES,"; 
        selectQuery = selectQuery + "FROM Products INNER JOIN ProductTypes ON Products.ProductTypeID,";
        selectQuery = selectQuery + "ProductTypes.ProductTypeID INNER JOIN, ";
        selectQuery = selectQuery + "Sales ON Sales.ProductID = Products.ProductID GROUP BY Products.ProductName ";
        selectQuery = selectQuery + "ProductTypes.ProductType, Sales.ProductID";
        selectQuery = selectQuery + " " + GlobalVariables.salesSearchCriteria;

        SqlConnection conn = ConnectionManager.DatabaseConnection();
        SqlDataReader rdr = null;

        try
        {
            conn.Open();
            SqlCommand cmd = new SqlCommand(selectQuery, conn);
            rdr = cmd.ExecuteReader();
            while (rdr.Read())
            {

                //Not sure if I need to create a seperate Class and then define the list (Class - ProductSales??)

                //Also need to include ListviewItems ??????

            }
            if (rdr != null)
                rdr.Close();
            conn.Close();
        }
        catch (Exception ex)
        {
            MessageBox.Show("Unsuccessful" + ex);
        }
    }

创建产品类,并获取如下示例所示的数据

    SqlDataReader reader = command.ExecuteReader();

    List<Product> lstProduct = new List<Product>();

    if (reader.HasRows)
    {
        while (reader.Read())
        {
            Product product = new Product();
            product.ProductName = reader.GetString(0);
            ...
            lstProduct.add(product);
        }
    }

    // Do what you want with lstProduct
SqlDataReader=command.ExecuteReader();
List lstProduct=新列表();
if(reader.HasRows)
{
while(reader.Read())
{
产品=新产品();
product.ProductName=reader.GetString(0);
...
lstProduct.add(产品);
}
}
//用你的产品做你想做的

是的,您需要创建另一个类。通过该查询获取数据,设置数据表并将数据表分配给Listview。

您可能会发现值得继续阅读。