Problem

The DialogJump function fails when attempting to navigate to root directories (e.g., C:\), throwing a UriFormatException with the message:

Invalid URI: A Dos path must be rooted, for example, 'c:\\'.

This occurs when paths are passed with a file: prefix but without proper URI formatting, such as file:C: (missing the trailing slash).

Root Cause

The CheckPath method in DialogJump.cs was using the Uri constructor directly:

var localPath = path.StartsWith("file:", StringComparison.OrdinalIgnoreCase)
 ? new Uri(path).LocalPath
 : path;

The Uri constructor throws UriFormatException when given malformed file URIs like file:C: (without trailing slash), causing DialogJump to fail for root directories.

Solution

Replaced the direct Uri constructor call with Uri.TryCreate() to gracefully handle malformed URIs:

string localPath;
if (path.StartsWith("file:", StringComparison.OrdinalIgnoreCase))
{
 // Try to create a URI from the path
 if (Uri.TryCreate(path, UriKind.Absolute, out var uri))
 {
 localPath = uri.LocalPath;
 }
 else
 {
 // If URI creation fails, treat it as a regular path
 // by removing the "file:" prefix
 localPath = path.Substring(5);
 }
}
else
{
 localPath = path;
}

This approach:

• ✅ Handles properly formatted file URIs using the standard Uri.LocalPath property
• ✅ Gracefully degrades for malformed URIs by stripping the file: prefix
• ✅ Allows the subsequent Directory.Exists() and File.Exists() checks to determine if the path is valid
• ✅ Maintains full backward compatibility with existing functionality

Testing

Verified the fix handles various path formats correctly:

• Root directories: file:C:, file:D: no longer throw exceptions
• Properly formatted URIs: file:///C:/, file://C:/ continue to work
• Regular paths: C:\, D:\ work as expected
• Shell paths: shell:MyComputerFolder continue to work

Fixes #[issue_number]

Fixes #4048

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