如何在范围内的Golang模板中显示变量

I have some code on the server:

...
c.HTML(http.StatusOK, "videos.html", gin.H{
    "files": files, //slice
    "errMessage": errMessage,
})
...

And I have some code on the client:

...
{{ range .files }}
<tr>
  <td>{{.}}</td>
  <td><a href="/download?filename={{.}}" style="color:blue;">Download</a></td>
  <td><a href="/delete?filename={{.}}" style="color:red;">Delete</a></td>
  <td><button id="{{.}}">Посмотреть</button></td>
  {{ if .errMessage }} <td style="color:red;">Processing...</td>
  {{ else }} <td>Done</td> {{ end }}
</tr>
{{ end }}
...

How to deal with .errMessage?

Can you show what is the error message? I deduce that your .errMessage is out of scope inside your {{ range .files }} syntax.

So to fix this problem, you will just declare your .errMessage on top of your {{ range .files }} syntax.

Though its not necessary to declare it on top, the main key here is that you should assign your .errMessage to another variable inside of your template.

It would look something like this ( based on your example ):

...
{{ $errMessage := .errMessage }}

{{ range .files }}
<tr>
  <td>{{.}}</td>
  <td><a href="/download?filename={{.}}" style="color:blue;">Download</a></td>
  <td><a href="/delete?filename={{.}}" style="color:red;">Delete</a></td>
  <td><button id="{{.}}">Посмотреть</button></td>
  {{ if $errMessage }} <td style="color:red;">Processing...</td>
  {{ else }} <td>Done</td> {{ end }}
</tr>
{{ end }}
...

Hope that helps! Cheers!