Implementieren von EntityDataSource Where IN Entity-SQL-Klausel

entitydatasource entity-framework entity-sql

Frage

Ich möchte eine Reihe von Werten an einen Parameter der EntityDataSource , zB:

Where="it.ORDER_ID IN {@OrderIdList}" (Dies ist eine Eigenschaft in der EntityDataSource)

<WhereParameters>
    <asp:ControlParameter 
       Name="OrderIdList" Type="Int16" 
       ControlID="OrderFilterControl" PropertyName="OrderIdList" 
    />
</WhereParameters>

Dies funktioniert nicht, da ORDER_ID vom Typ int32 und ich mehrere Werte übergeben muss, z. B. {1,2,3} usw

Als Nächstes habe ich versucht, die Where Klausel in Code- DropDownLists zu setzen. Dies funktioniert alles, außer ich kann keine Datenbindung für DropDownLists . Damit meine ich, dass kein Wert aus den gebundenen Dropdown-Listen im EntityDataSource Aktualisierungsereignis zurückgegeben wird.

Meine ideale Lösung wäre die Verwendung eines WhereParameter für EntityDataSource aber jede Hilfe wird geschätzt. Danke, Tony.


Ein vollständiges Codebeispiel unter Verwendung der AdventureWorks-Datenbank folgt:

Public Class EntityDataSourceWhereInClause
Inherits System.Web.UI.Page

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    CustomersEntityDataSource.Where = WhereClause ''# reset after each postback as its lost otherwise
End Sub

Private Sub cmdFilterCustomers_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles cmdFilterCustomers.Click
    Dim CustomerIdList As New Generic.List(Of Int32)
    For Each item As ListItem In CustomerIdCheckBoxList.Items
        If item.Selected Then
            CustomerIdList.Add(item.Value)
        End If
    Next

    Dim CustomerCsvList As String = String.Join(", ", CustomerIdList.Select(Function(o) o.ToString()).ToArray())
    WhereClause = "it.CustomerID IN {" & CustomerCsvList & "}"

    CustomersEntityDataSource.Where = WhereClause
    FormView1.PageIndex = 0

End Sub

''#  save between postbacks the custom Where IN clause
Public Property WhereClause() As String
    Get
        Return ViewState("WhereClause")
    End Get
    Set(ByVal value As String)
        ViewState.Add("WhereClause", value)
    End Set
End Property

Private Sub CustomersEntityDataSource_Updating(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.EntityDataSourceChangingEventArgs) Handles CustomersEntityDataSource.Updating
    Dim c = CType(e.Entity, EntityFrameworkTest.Customer)
    If c.Title.Length = 0 Then
        Response.Write("Title is empty string, so will save like this!")
    End If
End Sub

End Class

<%@ Page Language="vb" AutoEventWireup="false" CodeBehind="EntityDataSourceWhereInClause.aspx.vb"
Inherits="EntityFrameworkTest.EntityDataSourceWhereInClause" %>


<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
<form id="form1" runat="server">

<%''# filter control %>
<div>
    <asp:EntityDataSource ID="CustomerIdListEntityDataSource" runat="server" ConnectionString="name=AdventureWorksLT2008Entities"
        DefaultContainerName="AdventureWorksLT2008Entities" EnableFlattening="False"
        EntitySetName="Customers" Select="it.[CustomerID]" OrderBy="it.[CustomerID]">
    </asp:EntityDataSource>
    <asp:CheckBoxList ID="CustomerIdCheckBoxList" runat="server" DataSourceID="CustomerIdListEntityDataSource"
        DataTextField="CustomerID" DataValueField="CustomerID" RepeatDirection="Horizontal">
    </asp:CheckBoxList>
    <asp:Button ID="cmdFilterCustomers" runat="server" Text="Apply Filter" />
</div>

<%  
    ''# you get this error passing in CSV in the where clause
    ''# The element type 'Edm.Int32' and the CollectionType 'Transient.collection[Edm.String(Nullable=True,DefaultValue=,MaxLength=,Unicode=,FixedLength=)]' are not compatible. The IN expression only supports entity, primitive, and reference types.  Near WHERE predicate, line 6, column 15. 
    ''# so have coded it manually in code-behind Where="it.CustomerID IN {@OrderIdList}"
%>
<asp:EntityDataSource ID="CustomersEntityDataSource" runat="server" ConnectionString="name=AdventureWorksLT2008Entities"
    DefaultContainerName="AdventureWorksLT2008Entities" EnableFlattening="False"
    EnableUpdate="True" EntitySetName="Customers"
    AutoGenerateOrderByClause="false">
</asp:EntityDataSource>
<%''# updating works with DropDownLists until the Where clause is set in code %>
<asp:FormView ID="FormView1" runat="server" AllowPaging="True" CellPadding="4" DataKeyNames="CustomerID"
    DataSourceID="CustomersEntityDataSource" ForeColor="#333333">
    <EditItemTemplate>
        CustomerID:
        <asp:Label ID="CustomerIDLabel1" runat="server" Text='<%# Eval("CustomerID") %>' />
        <br />
        NameStyle:
        <asp:CheckBox ID="NameStyleCheckBox" runat="server" Checked='<%# Bind("NameStyle") %>' />
        <br />
        Title:
        <%''# the SelectedValue is not Bound to the EF object if the Where clause is updated in code-behind %>
        <asp:DropDownList ID="ddlTitleBound" runat="server" DataSourceID="TitleEntityDataSource"
            DataTextField="Title" DataValueField="Title" AutoPostBack="false" AppendDataBoundItems="true"
            SelectedValue='<%# Bind("Title") %>'>
        </asp:DropDownList>
        <asp:EntityDataSource ID="TitleEntityDataSource" runat="server" ConnectionString="name=AdventureWorksLT2008Entities"
            DefaultContainerName="AdventureWorksLT2008Entities" EnableFlattening="False"
            EntitySetName="Customers" Select="it.[Title]" GroupBy="it.[Title]" ViewStateMode="Enabled">
        </asp:EntityDataSource>
        <br />
        FirstName:
        <asp:TextBox ID="FirstNameTextBox" runat="server" Text='<%# Bind("FirstName") %>' />
        <br />
        MiddleName:
        <asp:TextBox ID="MiddleNameTextBox" runat="server" Text='<%# Bind("MiddleName") %>' />
        <br />
        LastName:
        <asp:TextBox ID="LastNameTextBox" runat="server" Text='<%# Bind("LastName") %>' />
        <br />
        Suffix:
        <asp:TextBox ID="SuffixTextBox" runat="server" Text='<%# Bind("Suffix") %>' />
        <br />
        CompanyName:
        <asp:TextBox ID="CompanyNameTextBox" runat="server" Text='<%# Bind("CompanyName") %>' />
        <br />
        SalesPerson:
        <asp:TextBox ID="SalesPersonTextBox" runat="server" Text='<%# Bind("SalesPerson") %>' />
        <br />
        EmailAddress:
        <asp:TextBox ID="EmailAddressTextBox" runat="server" Text='<%# Bind("EmailAddress") %>' />
        <br />
        Phone:
        <asp:TextBox ID="PhoneTextBox" runat="server" Text='<%# Bind("Phone") %>' />
        <br />
        PasswordHash:
        <asp:TextBox ID="PasswordHashTextBox" runat="server" Text='<%# Bind("PasswordHash") %>' />
        <br />
        PasswordSalt:
        <asp:TextBox ID="PasswordSaltTextBox" runat="server" Text='<%# Bind("PasswordSalt") %>' />
        <br />
        rowguid:
        <asp:TextBox ID="rowguidTextBox" runat="server" Text='<%# Bind("rowguid") %>' />
        <br />
        ModifiedDate:
        <asp:TextBox ID="ModifiedDateTextBox" runat="server" Text='<%# Bind("ModifiedDate") %>' />
        <br />
        <asp:LinkButton ID="UpdateButton" runat="server" CausesValidation="True" CommandName="Update"
            Text="Update" />
        &nbsp;<asp:LinkButton ID="UpdateCancelButton" runat="server" CausesValidation="False"
            CommandName="Cancel" Text="Cancel" />
    </EditItemTemplate>
    <EditRowStyle BackColor="#999999" />
    <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
    <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
    <ItemTemplate>
        CustomerID:
        <asp:Label ID="CustomerIDLabel" runat="server" Text='<%# Eval("CustomerID") %>' />
        <br />
        NameStyle:
        <asp:CheckBox ID="NameStyleCheckBox" runat="server" Checked='<%# Bind("NameStyle") %>'
            Enabled="false" />
        <br />
        Title:
        <asp:Label ID="TitleLabel" runat="server" Text='<%# Bind("Title") %>' />
        <br />
        FirstName:
        <asp:Label ID="FirstNameLabel" runat="server" Text='<%# Bind("FirstName") %>' />
        <br />
        MiddleName:
        <asp:Label ID="MiddleNameLabel" runat="server" Text='<%# Bind("MiddleName") %>' />
        <br />
        LastName:
        <asp:Label ID="LastNameLabel" runat="server" Text='<%# Bind("LastName") %>' />
        <br />
        Suffix:
        <asp:Label ID="SuffixLabel" runat="server" Text='<%# Bind("Suffix") %>' />
        <br />
        CompanyName:
        <asp:Label ID="CompanyNameLabel" runat="server" Text='<%# Bind("CompanyName") %>' />
        <br />
        SalesPerson:
        <asp:Label ID="SalesPersonLabel" runat="server" Text='<%# Bind("SalesPerson") %>' />
        <br />
        EmailAddress:
        <asp:Label ID="EmailAddressLabel" runat="server" Text='<%# Bind("EmailAddress") %>' />
        <br />
        Phone:
        <asp:Label ID="PhoneLabel" runat="server" Text='<%# Bind("Phone") %>' />
        <br />
        PasswordHash:
        <asp:Label ID="PasswordHashLabel" runat="server" Text='<%# Bind("PasswordHash") %>' />
        <br />
        PasswordSalt:
        <asp:Label ID="PasswordSaltLabel" runat="server" Text='<%# Bind("PasswordSalt") %>' />
        <br />
        rowguid:
        <asp:Label ID="rowguidLabel" runat="server" Text='<%# Bind("rowguid") %>' />
        <br />
        ModifiedDate:
        <asp:Label ID="ModifiedDateLabel" runat="server" Text='<%# Bind("ModifiedDate") %>' />
        <br />
        <asp:LinkButton ID="EditButton" runat="server" CausesValidation="False" CommandName="Edit"
            Text="Edit" />
    </ItemTemplate>
    <PagerSettings Position="Top" />
    <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
    <RowStyle BackColor="#F7F6F3" ForeColor="#333333" />
</asp:FormView>
</form>

Beliebte Antwort

Im Folgenden finden Sie eine alternative Lösung, wenn Paging deaktiviert ist und Sie immer noch ein Problem haben:

Private Sub DetailsView1_ModeChanged(sender As Object, e As System.EventArgs) Handles DetailsView1.ModeChanged
        EntityDataSource1.Where = "it.[ID]=" & Me.lstFilter.SelectedValue  ' DetailView.Edit work-around for lost context: Reset bound EntityDataSource.Where
Sub


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Lizenziert unter: CC-BY-SA with attribution
Nicht verbunden mit Stack Overflow
Ist diese KB legal? Ja, lerne warum