implement radzen text editor.

Oqtane.Client/Modules/Controls/FileManagerDialog.razor

@@ -0,0 +1,45 @@
+@namespace Oqtane.Modules.Controls
+@using System.IO
+@using Radzen
+@using Radzen.Blazor
+@inject DialogService DialogService
+@inject IStringLocalizer<Oqtane.Modules.Controls.RadzenTextEditor> Localizer
+
+<div class="d-flex">
+    <FileManager @ref="_fileManager" Filter="@Filters" />
+</div>
+<div class="d-flex">
+    <ModuleMessage Message="@_message" Type="MessageType.Warning"></ModuleMessage>
+</div>
+<div class="mt-1 text-end">
+    <RadzenButton Text="OK" Click=@OnOkClick />
+    <RadzenButton Text="Cancel" Click=@OnCancelClick ButtonStyle="ButtonStyle.Secondary" />
+</div>
+@code {
+    private FileManager _fileManager;
+    private string _message = string.Empty;
+
+    [Parameter]
+    public string Filters { get; set; }
+
+    private void OnCancelClick()
+    {
+        DialogService.Close(null);
+    }
+
+    private void OnOkClick()
+    {
+        _message = string.Empty;
+        var file = _fileManager.GetFile();
+        if (file != null)
+        {
+            var result = $"<img src=\"{file.Url}\" style=\"max-width: 100%\" alt=\"{file.Name}\" />";
+            DialogService.Close(result);
+        }
+        else
+        {
+            _message = Localizer["Message.Require.Image"];
+            StateHasChanged();
+        }
+    }
+}