visual studio 2019 or 2022, Edge Browser for javascript debugging stops at wrong line

Question

Using VS 2019 or 2022 community edition, I can debug javascript using IE just fine, however when using Chrome or Edge (chromium) the wrong line of code is shown at the breakpoint. The line of code highlighted is about 50 lines below the actual line.

With this html file, the breakpoint occurs 5 lines below "debugger;"

With this html file, the breakpoint occurs correctly on "debugger;"

Any ideas? Both html files work correctly in IE, but not in Edge. Using Visual Studio Community 2019 Version 16.11.6

This is a verified issue. See: https://developercommunity.visualstudio.com/t/Edge-Browser-for-javascript-debugging-st/1628778 for more info, and if this is affecting you, please add a comment there to let Microsoft know I'm not the only one. Seems they think it's a low priority

Answer 1

The render override below helped, but didn't always work, and could cause side effects, so I removed it. Instead I removed unneeded blank lines between tags from my MasterPage, then added extra lines at the top of the aspx page after the first line (<%@ Page Title.....) and before the first <asp:content line. I added "debugger;" to as the first line of JavaScript code that gets executed. Then load the page and see where the breakpoint in Visual Studio shows. Adding lines to the top of the aspx page will move the breakpoint up, and adding lines to the Masterpage (outside of tags) will move it down.

Once you determine the number of lines needed, add them to the top of any aspx page you are debugging and visual studio should stop at the "debugger" line..

--- old answer --- I have been able to override Render to mostly correct the problem. It's not perfect, but for most javascript sources (some may be off a line or two) it works. I created a MyPage class that inherits from System.Web.UI.Page, an added the code below. All your aspx.cs pages will need to inherit from MyPage.

It basically eliminates new lines and mostly avoids the problem. "IsDevelopmentSite" is a variable in my app that identifies that I'm working on a Dev computer, so this only runs in development.

        protected override void Render(HtmlTextWriter writer)
        {
            StringBuilder sb = new StringBuilder();
            HtmlTextWriter tw = new HtmlTextWriter(new System.IO.StringWriter(sb));
            base.Render(tw);
            string sContent = sb.ToString();

            if (IsDevelopmentSite && Request.Browser.Browser != "InternetExplorer")
            {
                var headEnd = sContent.IndexOf("</head>");
                if (headEnd > -1)
                {
                    string head = sContent.Substring(0, headEnd);
                    int script;
                    int style;
                    int start;
                    int end;
                    string h = "";
                    do
                    {
                        // remove all cr lf, outside <script> and <style> tags, and some cr lf within script and style.
                        script = head.IndexOf("<script");
                        style = head.IndexOf("<style");
                        if (style == -1 && script == -1)
                            break;

                        if (style == -1 || (script != -1 && script < style))
                        {
                            start = script;
                            end = head.IndexOf("</script>", start) + 9;

                            if (end < 9)
                                break; // no closing tag
                            h += head.Substring(0, start).Replace("\r\n", " ") + head.Substring(start, end - start).Replace(">\r\n", ">");
                        }
                        else
                        {
                            start = style;
                            end = head.IndexOf("</style>", start) + 8;
                            if (end < 8)
                                break; // no closing tag
                            h += head.Substring(0, start).Replace("\r\n", " ") + head.Substring(start, end - start).Replace("\r\n\r\n", "\r\n").Replace("\">\r\n", "\">");
                        }
                        head = head.Substring(end);
                    } while (true);
                    sContent = h + head + sContent.Substring(headEnd);
                }
            }
            writer.Write(sContent);
        }