fix pager con selettore tendina

MP.Stats/Components/DataPager.razor

@@ -1,21 +1,42 @@
 <div class="input-group input-group-sm">
-    <input @bind-value="numRecord" @bind-value:event="oninput" type="text" class="form-control" />
-    <div class="input-group-append">
-        <button @onclick="reportChange" class="btn btn-success input-group-text"># record</button>
-        @*<span class="input-group-text"># record</span>*@
-    </div>
+    row/pag:&nbsp;
+    <select @bind="@numRecord" class="form-control form-control-sm">
+        <option value="5">5</option>
+        <option value="10">10</option>
+        <option value="25">25</option>
+        <option value="50">50</option>
+        <option value="100">100</option>
+    </select>
 </div>
 
 @code {
 
+    protected int _numRecord { get; set; } = 10;
+
     [Parameter]
-    public int numRecord { get; set; } = 10;
+    public int numRecord
+    {
+        get
+        {
+            return _numRecord;
+        }
+        set
+        {
+            bool doReport = !_numRecord.Equals(value);
+            _numRecord = value;
+            if (doReport)
+            {
+                reportChange();
+            }
+        }
+    }
 
     [Parameter]
     public EventCallback<int> numRecordChanged { get; set; }
 
-    private async Task reportChange()
+    private void reportChange()
     {
-        await numRecordChanged.InvokeAsync(numRecord);
+        numRecordChanged.InvokeAsync(numRecord);
     }
+
 }