MicrosoftEdge / MicrosoftEdge/WebView2Feedback

[Problem/Bug]: When I call a method of a host object that returns a simple dictionary<string,string>, the returned value is always null

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#5,217 1 comment 0 reactions 1 assignee View on GitHub

@prija-microsoft is already working on this.

Since Apr 28, 2025.

bug
Dominant language
PowerShell
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Description

What happened?

I am using the following project:
https://github.com/rgwood/MinimalWebView

I have updated the SDK to the latest version (it also fails with older versions).

I add a simple hostobject like this:

`
[ComVisible(true)]
[ClassInterface(ClassInterfaceType.AutoDual)]
public class Prueba
{

public object Hacer(object obj)
{
    Dictionary<string, string> dic = new Dictionary<string, string>();

    dic.Add("texto", "hola");
    dic.Add("numeros", "sdsd");

    return dic;
}

}`

And in JS I do:

let valor = window.chrome.webview.hostObjects.sync["Prueba"].Hacer(123)

Expected value: valor = { texto: "hola", numeros: "sdsd" }
I received always: valor = null

Importance

Low. My app is not very affected, or this only affects development.

Runtime Channel

Stable release (WebView2 Runtime)

Runtime Version

No response

SDK Version

No response

Framework

Other

Operating System

Windows 10

OS Version

No response

Repro steps

I am using the following project:
https://github.com/rgwood/MinimalWebView

I have updated the SDK to the latest version (it also fails with older versions).

I add a simple hostobject like this:

`
[ComVisible(true)]
[ClassInterface(ClassInterfaceType.AutoDual)]
public class Prueba
{

public object Hacer(object obj)
{
    Dictionary<string, string> dic = new Dictionary<string, string>();

    dic.Add("texto", "hola");
    dic.Add("numeros", "sdsd");

    return dic;
}

}`

And in JS I do:

let valor = window.chrome.webview.hostObjects.sync["Prueba"].Hacer(123)

Expected value: valor = { texto: "hola", numeros: "sdsd" }
I received always: valor = null

Repros in Edge Browser

No, issue does not reproduce in the corresponding Edge version

Regression

No, this never worked

Last working version (if regression)

No response

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Assessment

This issue has not been assessed yet.

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