JS Interop in Blazor

1. Collocated JS Modules

Always use collocated .razor.js files with export — never global window.* functions or <script> tags.

// ChartPanel.razor.js — placed next to ChartPanel.razor
export function initialize(canvas, dotNetRef) { /* ... */ }
export function updateData(points) { /* ... */ }
export function dispose() { /* ... */ }

Import paths: same project = "./Components/ChartPanel.razor.js", RCL = "./_content/{AssemblyName}/...".

2. Lifecycle Timing

All JS interop must happen in OnAfterRenderAsync or event handlers — never in OnInitialized, OnParametersSet, or constructors. JS is not available during server prerendering.