Preserve quote style when rendering markup content

[captainsafia]

Fixes #20950.

When a component renders static markup like:

<input onfocus='alert(""Test"");' />
<input onfocus=""alert(""Test"");"" />
<input onfocus=""alert('Test');"" />
<p data-options='{direction: ""fromtop"", animation_duration: 25, direction: ""reverse""}'></p>

The Razor compiler interprets this collection of lines as a MarkupBlock. Unlike tag helper attributes, we don't store any information about what type of quote is used in the attributes (typically represented with an AttributeStructure enum). Instead, we indiscriminately use double quotes for all attributes on an HTML element within a markup block.

aspnetcore/src/Razor/Microsoft.AspNetCore.Razor.Language/src/Components/ComponentMarkupBlockPass.cs

Lines 330 to 335 in 3d1c0e3

	Builder.Append("=\"");
	// Visit Children
	base.VisitDefault(node);
	Builder.Append('"');

This causes issues in particular if a markup element like <input onfocus='alert("Test");' /> is rendered because we produce the incorrectly quoted <input onfocus="alert("Test");" />. To resolve this, we add a check when constructing the attribute string to preserve the original quote style designated by the user.

[SteveSandersonMS]

Looks great!

[phlexpay]

data-hs-header-options='{
"fixMoment": 0,
"fixEffect": "slide"
}'

this as an attribute on a normal html element (in this case

) is still causing problems. The content is coming up as null when I try to get the string from the attribute.

[ghost]

Hi @phlexpay. It looks like you just commented on a closed PR. The team will most probably miss it. If you'd like to bring something important up to their attention, consider filing a new issue and add enough details to build context.