update CmlLibWinFormSample

fix null version in ChangeLogs
RiversideValley · Jun 2, 2021 · fe8aae0 · fe8aae0
1 parent 0463b7c
commit fe8aae0
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/CmlLibWinFormSample/ChangeLog.cs b/CmlLibWinFormSample/ChangeLog.cs
@@ -23,9 +23,12 @@ private async void ChangeLog_Load(object sender, EventArgs e)
 
         private async void btnLoad_Click(object sender, EventArgs e)
         {
-            btnLoad.Enabled = false;
+            var version = listBox1.SelectedItem?.ToString();
+            if (string.IsNullOrEmpty(version))
+                return;
 
-            var version = listBox1.SelectedItem.ToString();
+            btnLoad.Enabled = false;
+
             var body = await changelogs.GetChangelogHtml(version);
             webBrowser1.DocumentText = body;