實體框架SaveChangesAsync不更新數據庫

Question

發票分類實體：

public class InvoiceCategory 
{  
    [Key] 
    Public int InvoiceCategoryID { get; set; } 

    [Required] 
    public string CategoryName { get; set; } 
} 

發票項目實體

public class InvoiceItem 
{ 
    [Key] 
    public int InvoiceItemID { get; set; } 

    [Required] 
    public int InvoiceID { get; set; } 

    [Required] 
    [Display(Name = "Date Completed")] 
    [DataType(DataType.Date)] 
    public DateTime? Date { get; set; } 

    [StringLength(50)] 
    public string InvoiceCategory { get; set; } 

    [Required] 
    [StringLength(200)] 
    public string Description { get; set; } 

    [Required] 
    [StringLength(20)] 
    public string Unit { get; set; }  

    [Required] 
    [DataType(DataType.Currency)] 
    [DisplayFormat(ApplyFormatInEditMode = false, DataFormatString = "{0:c}")] 
    public decimal Price { get; set; } 

    [Required] 
    [DefaultValue(1)] 
    public decimal? Quantity { get; set; } 

    public virtual Invoice Invoice { get; set; }  
} 

發票分類，編輯，查看

@model Accounts.Models.InvoiceCategory 
<h2>Settings</h2> 
<br /> 
<h4>Invoice Categories</h4> 
<hr /> 
<form asp-action="Edit"> 
    <div asp-validation-summary="ModelOnly" class="text-danger"></div> 
    @(Html.Kendo().Grid<Accounts.Models.InvoiceCategory>() 
       .Name("InvoiceCategory") 
       .ToolBar(tools => 
       { 
        tools.Create().Text("New Category"); 
       }) 
       .Editable(editable => editable.Mode(GridEditMode.InCell).CreateAt(GridInsertRowPosition.Bottom).DisplayDeleteConfirmation(false)) 
       .Columns(columns => 
       { 
        columns.Bound(p => p.InvoiceCategoryID).Hidden().ClientTemplate("#= InvoiceCategoryID #" + 
        "<input type='hidden' name='[#= index(data)#].InvoiceCategoryID' value='#= InvoiceCategoryID #'/>" 
       ); 

        columns.Bound(p => p.CategoryName).ClientTemplate("#= CategoryName #" + 
        "<input type='hidden' name='[#= index(data)#].CategoryName' value='#= CategoryName #'/>" 
       ); 
        columns.Template("<a class='btn btn-danger btn-sm k-grid-delete'><span class='glyphicon glyphicon-trash'></span> </a>").Width(50); 
       }) 
       .DataSource(dataSource => dataSource.Ajax() 
        .Model(model => 
        { 
         model.Id(p => p.InvoiceCategoryID); 
         model.Field(p => p.InvoiceCategoryID).Editable(false); 
        }) 
        .Read(read => read.Action("InvoiceCategories_Read", "Settings"))      
        .ServerOperation(false) 
      ).Deferred() 
    ) 
    <br /> 
    <button type="submit" class="btn btn-success"><span class="glyphicon glyphicon-floppy-disk" style="vertical-align:middle;margin-top:-5px"></span> Save</button> 
</form> 
@section Scripts { 
    @Html.Kendo().DeferredScripts() 

    <script> 
     function index(dataItem) { 
      var data = $("#InvoiceCategory").data("kendoGrid").dataSource.data(); 
      return data.indexOf(dataItem); 
     } 
    </script> 

    <style> 
     .k-grid { 
      width: 280px; 
     } 
    </style> 
} 

控制器發票類別更新方法：

[HttpPost] 
[ValidateAntiForgeryToken] 
public async Task<IActionResult> Edit(IEnumerable<InvoiceCategory> invoiceCategory) 
{ 
    if (ModelState.IsValid) 
    { 
     try 
     { 
      _context.InvoiceCategory.UpdateRange(invoiceCategory); 
      _context.SaveChangesAsync(); 
     } 
     catch (Exception ex) 
     { 
      ... 
     } 
    } 
} 

的值在視圖中被改變和變化被髮送到然而的更改不會頒佈給數據庫出於某種原因控制器的編輯方法用保存方法。

實體框架不支持像我這樣沒有整數標識列的查找表嗎？還是我在做一些愚蠢的事情？

Answer 1

基本上你要做的是更新名爲InvoiceCategory的表的主鍵。無論如何，在你的代碼的上下文中，如果你在數據庫的背景下思考它，這是沒有意義的。主鍵是記錄的唯一標識符。你不應該能夠更新它。

作爲便箋，無論何時使用async您都應至少使用一次使用await。否則你的方法會同步執行。在你的情況下，缺少的await是這樣的：

await _context.SaveChangesAsync(); 

更新

我認爲你需要沿着以下的說法：

[HttpPost] 
[ValidateAntiForgeryToken] 
public async Task<IActionResult> Edit(IEnumerable<InvoiceCategory> invoiceCategories) 
{ 
    if (ModelState.IsValid) 
    { 
     try 
     { 
      foreach(var invoiceCategory in invoiceCategories) 
      { 
       if(invoiceCategory.InvoiceCategoryID == 0) 
       { 
        _context.InvoiceCategory.Add(invoiceCategory);  
       } 
       else 
       { 
        _context.InvoiceCategory.Update(invoiceCategory); 
       } 
      } 
      await _context.SaveChangesAsync(); 
     } 
     catch (Exception ex) 
     { 
      ... 
     } 
    } 
}