cefsharp/CefSharp · error · ArgumentNullException

name

Error message

name

What it means

Thrown by JavascriptObjectRepository.Register when the name argument is null. The name is the JavaScript global object key under which the bound .NET object is exposed to the page; a null name cannot be registered, so Register fails fast with ArgumentNullException before touching the object table. Register then calls Freeze() and performs further validation.

Source

Thrown at CefSharp/Internals/JavascriptObjectRepository.cs:205

            {
                Id = id,
                RootObject = rootObject
            };

            objects[id] = result;

            return result;
        }

#if NETCOREAPP
        public void Register(string name, object value, BindingOptions options)
#else
        public void Register(string name, object value, bool isAsync, BindingOptions options)
#endif
        {
            if (name == null)
            {
                throw new ArgumentNullException("name");
            }

            if (value == null)
            {
                throw new ArgumentNullException("value");
            }

            Freeze();

            //Enable WCF if not already enabled - can only be done before the browser has been initliazed
            //if done after the subprocess won't be WCF enabled it we'll have to throw an exception
#if NETCOREAPP
            var isAsync = true;
#else
            if (!IsBrowserInitialized && !isAsync)
            {
                CefSharpSettings.WcfEnabled = true;
            }

View on GitHub (pinned to 16bc6e0711)

Solutions

1. Ensure the name is a non-null, non-empty, unique string before calling Register.
2. Validate names from dynamic sources (metadata/dictionary) and skip or default null entries.
3. Check uniqueness against already-bound names since a later check throws ArgumentException on duplicates.

Example fix

// before
repo.Register(name, myObject, new BindingOptions());

// after
if (string.IsNullOrEmpty(name)) throw new ArgumentException("Binding name required.");
repo.Register(name, myObject, new BindingOptions());

if (string.IsNullOrEmpty(name))
{
    throw new ArgumentException("Binding name is required.");
}
repo.Register(name, value, new BindingOptions());

static bool IsValidBindingName(string name) => !string.IsNullOrEmpty(name);

When it happens

Trigger: Calling browser.JavascriptObjectRepository.Register(null, obj, ...) or the BindingOptions overload with a name variable that was never assigned. Common in dynamic binding loops where the name comes from a dictionary/metadata source that yielded null.

Common situations: Binding objects in a loop driven by external metadata where a name field is missing; a config-driven binding list with an empty key; copy-paste that dropped the name argument; DI resolving a name that returned null.

Related errors

• value
• Please provide a valid array
• converter
• manager
• Please provide a valid filePath

AI-assisted analysis of cefsharp/CefSharp@16bc6e0711 (2026-08-13). Data as JSON: /api/errors/c380fe2b1790a534. Report an issue: GitHub.