Blazor jquery select2 双向绑定

Question

我在 blazor 服务器端使用了 jquery select2 如何绑定选定的值

<InputSelect class="form-control select2" @bind-Value="@purchaseSearch.PriorityId" id="search-priorityId">
<option value="">All</option>
@foreach (var priority in priorities)
{
<option value="@priority.Id">@priority.Name</option>
}
</InputSelect>

Answer 1

我为 blazor 创建了一个带有 select2 库的自定义组件选择。我希望这是你的榜样。- Select2.razor：

@typeparam TValue
@inherits InputBase<TValue>
@if (!string.IsNullOrWhiteSpace(Label))
{
    <label class="form-control-label" for="@Id">
        @Label
        @if (Required)
        {
            <font color="red">(*)</font>
        }
    </label>
}
else
{
    <LabelFor FieldIdentifier="FieldIdentifier"></LabelFor>
}
<select id="@Id" class="form-control select2" style="width: 100%;" >
    <option @key="null" value="null">--- Ch?n ---</option>
    @if (Datasource != null)
        @foreach (var item in Datasource)
        {
            if (item.Key == Value?.ToString())
            {
                <option @key="@item.Key" value="@item.Key" selected="selected">
                    @((MarkupString)@item.Value)
                </option>
            }
            else
            {
                <option @key="@item.Key" value="@item.Key">
                    @((MarkupString)@item.Value)
                </option>
            }
        }
</select>
<div class="form-control-validation">
    <CustomValidationMessage  Field="FieldIdentifier" TValue="string" />
</div>

• Select2.razor.cs

  public partial class SelectWithFilter<TValue> : InputBase<TValue>
  {
          [Parameter] public string Id { get; set; }
          [Parameter] public string Label { get; set; }
          [Parameter] public bool Required { get; set; }
          //[Parameter] public Expression<Func<string>> ValidationFor { get; set; }
          [Parameter] public ICollection<KeyValuePair<string, string>> Datasource { get; set; }
          [Inject] IJSRuntime JSRuntime { get; set; }
          public DotNetObjectReference<SelectWithFilter<TValue>> DotNetRef;
          protected override bool TryParseValueFromString(string value, out TValue result, out string validationErrorMessage)
          {
              if (value == "null")
              {
                  value = null;
              }
              if (typeof(TValue) == typeof(string))
              {
                  result = (TValue)(object)value;
                  validationErrorMessage = null;
  
                  return true;
              }
              else if (typeof(TValue) == typeof(int) || typeof(TValue) == typeof(int?))
              {
                  int.TryParse(value, NumberStyles.Integer, CultureInfo.InvariantCulture, out var parsedValue);
                  result = (TValue)(object)parsedValue;
                  validationErrorMessage = null;
  
                  return true;
              }
  
              throw new InvalidOperationException($"{GetType()} does not support the type '{typeof(TValue)}'.");
          }
  
          protected override void OnInitialized()
          {
              base.OnInitialized();
              DotNetRef = DotNetObjectReference.Create(this);
          }
  
          protected override async Task OnAfterRenderAsync(bool firstRender)
          {
              await base.OnAfterRenderAsync(firstRender);
              if (firstRender)
              {
                  await JSRuntime.InvokeVoidAsync("select2Component.init", Id);
                  await JSRuntime.InvokeVoidAsync("select2Component.onChange", Id, DotNetRef, "Change_SelectWithFilterBase");
              }
          }
  
          [JSInvokable("Change_SelectWithFilterBase")]
          public void Change(string value)
          {
              if (value == "null")
              {
                  value = null;
              }
              if (typeof(TValue) == typeof(string))
              {
                  CurrentValue = (TValue)(object)value;
              }
              else if (typeof(TValue) == typeof(int))
              {
                  int.TryParse(value, NumberStyles.Integer, CultureInfo.InvariantCulture, out var parsedValue);
                  CurrentValue = (TValue)(object)parsedValue;
              }
              else if (typeof(TValue) == typeof(int?))
              {
                  if (value == null)
                  {
                      CurrentValue = (TValue)(object)null;
                  }
                  else
                  {
                      int.TryParse(value, NumberStyles.Integer, CultureInfo.InvariantCulture, out int parsedValue);
                      CurrentValue = (TValue)(object)parsedValue;
                  }
              }
          }
      }
  

• js：

@typeparam TValue
@inherits InputBase<TValue>
@if (!string.IsNullOrWhiteSpace(Label))
{
    <label class="form-control-label" for="@Id">
        @Label
        @if (Required)
        {
            <font color="red">(*)</font>
        }
    </label>
}
else
{
    <LabelFor FieldIdentifier="FieldIdentifier"></LabelFor>
}
<select id="@Id" class="form-control select2" style="width: 100%;" >
    <option @key="null" value="null">--- Ch?n ---</option>
    @if (Datasource != null)
        @foreach (var item in Datasource)
        {
            if (item.Key == Value?.ToString())
            {
                <option @key="@item.Key" value="@item.Key" selected="selected">
                    @((MarkupString)@item.Value)
                </option>
            }
            else
            {
                <option @key="@item.Key" value="@item.Key">
                    @((MarkupString)@item.Value)
                </option>
            }
        }
</select>
<div class="form-control-validation">
    <CustomValidationMessage  Field="FieldIdentifier" TValue="string" />
</div>