private static MarkupMinimizedTagHelperDirectiveAttributeSyntax RewriteToMinimizedDirectiveAttribute(
MarkupMinimizedAttributeBlockSyntax attributeBlock,
TryParseResult result)
{
//
// Consider, <Foo @bind:param />
// We're now going to rewrite @bind:param from a regular MarkupAttributeBlock to a MarkupTagHelperDirectiveAttribute.
// We need to split the name "@bind:param" into four parts,
// @ - Transition (MetaCode)
// bind - Name (Text)
// : - Colon (MetaCode)
// param - ParameterName (Text)
//
var attributeName = result.AttributeName;
var attributeNameSyntax = attributeBlock.Name;
var transition = SyntaxFactory.RazorMetaCode(
new SyntaxList <SyntaxToken>(SyntaxFactory.MissingToken(SyntaxKind.Transition)));
RazorMetaCodeSyntax colon = null;
MarkupTextLiteralSyntax parameterName = null;
if (attributeName.StartsWith("@", StringComparison.Ordinal))
{
attributeName = attributeName.Substring(1);
var attributeNameToken = SyntaxFactory.Token(SyntaxKind.Text, attributeName);
attributeNameSyntax = SyntaxFactory.MarkupTextLiteral().AddLiteralTokens(attributeNameToken);
var transitionToken = SyntaxFactory.Token(SyntaxKind.Transition, "@");
transition = SyntaxFactory.RazorMetaCode(new SyntaxList <SyntaxToken>(transitionToken));
}
if (attributeName.IndexOf(':') != -1)
{
var segments = attributeName.Split(new[] { ':' }, 2);
var attributeNameToken = SyntaxFactory.Token(SyntaxKind.Text, segments[0]);
attributeNameSyntax = SyntaxFactory.MarkupTextLiteral().AddLiteralTokens(attributeNameToken);
var colonToken = SyntaxFactory.Token(SyntaxKind.Colon, ":");
colon = SyntaxFactory.RazorMetaCode(new SyntaxList <SyntaxToken>(colonToken));
var parameterNameToken = SyntaxFactory.Token(SyntaxKind.Text, segments[1]);
parameterName = SyntaxFactory.MarkupTextLiteral().AddLiteralTokens(parameterNameToken);
}
var rewritten = SyntaxFactory.MarkupMinimizedTagHelperDirectiveAttribute(
attributeBlock.NamePrefix,
transition,
attributeNameSyntax,
colon,
parameterName);
rewritten = rewritten.WithTagHelperAttributeInfo(
new TagHelperAttributeInfo(result.AttributeName, parameterName?.GetContent(), result.AttributeStructure, result.IsBoundAttribute, isDirectiveAttribute: true));
return(rewritten);
}
private static MarkupTagHelperAttributeValueSyntax RewriteAttributeValue(TryParseResult result, RazorBlockSyntax attributeValue)
{
var rewriter = new AttributeValueRewriter(result);
var rewrittenValue = attributeValue;
if (result.IsBoundAttribute)
{
// If the attribute was requested by a tag helper but the corresponding property was not a
// string, then treat its value as code. A non-string value can be any C# value so we need
// to ensure the tree reflects that.
rewrittenValue = (RazorBlockSyntax)rewriter.Visit(attributeValue);
}
return(SyntaxFactory.MarkupTagHelperAttributeValue(rewrittenValue.Children));
}
public AttributeValueRewriter(TryParseResult result)
{
_tryParseResult = result;
}
public bool SetTryParseResult(string res)
{
UiDispatcher?.Invoke(() => { TryParseResult.Add(res); }); return(true);
}
