我的剃须刀代码遮盖了这个telerik下拉列表:
<TelerikDropDownList Data="@BkAccounts" TextField="@(nameof(BkAccounts.DisplayField))" ValueField="@(nameof(BkAccounts.BIC))" Value=1 ></TelerikDropDownList>
它指向此类:
public class BkAccounts
{
public int Id { get; set; }
public string Iban { get; set; }
public string BIC{ get; set; }
public string DisplayField{ get { return this.Iban + " - " + this.BIC; } }
}
如果我这样写,则下拉列表无法正确填充。
如果我这样更改:
<TelerikDropDownList Data="@BkAccounts" TextField="@(nameof(BkAccounts.DisplayField))" ValueField="@(nameof(BkAccounts.Id))" Value=1 ></TelerikDropDownList>
效果很好。
实际上,我想从此BkAccounts类中删除ID字段,但是我无法正确填充DDL。我错过了什么?根据Telerik的文档,TextField可以接受字符串字段,因此它不应该是格式问题...
编辑:这2个摘要之间的区别在于:ValueField =“ @(nameof(BkAccounts.BIC)--->不会填充ValueField =“ @(nameof(BkAccounts.Id)--->像超级按钮一样填充
我开始强烈怀疑问题出在Telerik一方。这是他们的示例TelerikDropDownList代码,来自https://demos.telerik.com/blazor-ui/dropdownlist/overview
@page "/dropdownlist/overview"
@page "/dropdownlist/index"
@using TelerikBlazorDemos.Shared
<div class="example-box-wrapper">
<div class="example">
<div class="mb-4">T-Shirt size:</div>
<TelerikDropDownList Data="@Data"
@bind-Value=@SelectedSizeMetric
PopupHeight=""
DefaultText="Select your T-shirt size"
ValueField="SizeMetric" TextField="SizeText">
</TelerikDropDownList>
</div>
<div class="ml-4">
Selected Size Number: <strong>@SelectedSizeMetric</strong>
</div>
</div>
@code {
public IEnumerable<Size> Data { get; set; }
public bool AllowCustom { get; set; } = true;
public int? SelectedSizeMetric { get; set; }
public string SelectedSize { get; set; }
public class Size
{
public string SizeText { get; set; }
public int? SizeMetric { get; set; }
}
protected override void OnInitialized()
{
List<Size> sizes = new List<Size>();
sizes.Add(new Size()
{
SizeText = "X-Small",
SizeMetric = 3
});
sizes.Add(new Size()
{
SizeText = "Small",
SizeMetric = 6
});
sizes.Add(new Size()
{
SizeText = "Medium",
SizeMetric = 8
});
sizes.Add(new Size()
{
SizeText = "Large",
SizeMetric = 10
});
sizes.Add(new Size()
{
SizeText = "X-Large",
SizeMetric = 12
});
Data = sizes.AsQueryable();
base.OnInitialized();
}
}
可以正常使用。但是,如果我更改:
ValueField="SizeMetric" //int type
for:
ValueField="SizeText" //string type
它不再起作用了...我得到:System.InvalidCastException`:'无法将类型为'System.String'的对象转换为类型为'System.Nullable`1 [System.Int32]'。'
我从Telerik论坛得到了答案:https://www.telerik.com/forums/telerikdropdownlist-throwing-a-system-invalidcastexception-when-valuefield-is-a-string#tnrnhB1ghkmWxEUE24wUhA
我需要添加到我的TelerikDropDownList代码中:@ bind-Value = @ SelectedBankAccount并将其声明为字符串属性到viewmodel中]