Question

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如果使用ORM连接，此代码将如何显示

Imports System.Data
Imports System.Data.SqlClient

Partial Class _Default
    Inherits System.Web.UI.Page

    Public Sub OpenDBproduct()
        Dim ProductConnection As SqlConnection = New SqlConnection(ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString)

        Dim ProductReader As SqlDataReader
        Dim ProductCommand As SqlCommand

        Dim ProductSQL As String = ""
        ProductSQL = "SELECT * FROM table1 ORDER BY PName DESC;"
        ProductCommand = New SqlCommand(ProductSQL, ProductConnection)

        'Prøv at åben Connection.
        Try
            ProductConnection.Open()
            ProductReader = ProductCommand.ExecuteReader(CommandBehavior.CloseConnection)
            'Hvis der er data, udskriv da dataen.
            If ProductReader.HasRows() Then

                Response.Write("<h2>Produkter</h2>")
                Response.Write("<table style=""width:340px; border:0px;""><tr>")

                Do While ProductReader.Read()
                    Response.Write("<td colspan=""3""><br /></td>")
                    Response.Write("</tr><tr>")
                    Response.Write("<td style=""width:10px;""></td>")
                    Response.Write("<td><div style=""width:52px; text-align:center;""><span class=""""># " & ProductReader("PName") & "</span></div></td>")
                    Response.Write("<td class=""""><span class="""">" & ProductReader("PName") & "</span><br /><span class="""">" & ProductReader("PPrice") & "</span><br /><span class=""""><b>" & ProductReader("Pean") & "</b></span></td>")
                    Response.Write("</tr><tr>")
                    Response.Write("<td colspan=""3""><br />" & ProductReader("PDescription") & "</td>")
                    Response.Write("</tr><tr>")
                    Response.Write("<td style=""border-bottom:dashed 2px #FFA902;"" colspan=""3""><br /></td>")
                    Response.Write("</tr><tr>")

                Loop
                Response.Write("</tr></table>")
                Response.Write("Slutning")
            Else
                'Hvis der ikke er data, lav en fejl tekst.
                Response.Write("<table style=""width:340px; border:0px;""><tr><td>")
                Response.Write("Der findes ingen produkter.")
                Response.Write("<br /><br />")
                Response.Write("Slutning")
                Response.Write("</td></tr></table>")
            End If

        Catch ex As Exception
            Console.WriteLine(ex.Message)

        Finally
            'Lukker Connection, Reader og Sletter Hukommelse.
            If Not ProductReader Is Nothing Then
                ProductReader.Dispose()
            End If
            If Not ProductConnection Is Nothing Then
                ProductConnection.Dispose()
            End If

        End Try
    End Sub
End Class

Answer 1

如果我理解正确的话 - 如果您使用某些ORM（例如EntityFramework或NHibernate），则会询问有关更改的代码。如此简短的描述（抱歉C＃语法）：
连接将更改为强类型代码，不带SQL字符串。

using (var dbContext = new ProductEntites())
{
   var dbSelect = dbContext.Products.OrderBy(x=>x.PName);

Do-While将更改为foreach(var product in dbSelect)

所有ProductReader("PDescription")都会更改为product.PDescription（无字符串！）

使用ORM

使用强类型类的所有利润（它们将使用Visual Studio工具生成）更安全
SQL注入的参数检查是自动进行的

SQLConnectionString到ORM如何

1 个答案: