public virtual void WriteAttribute(string name,
PositionTagged <string> prefix,
PositionTagged <string> suffix,
params AttributeValue[] values)
{
WriteAttributeTo(Output, name, prefix, suffix, values);
}
public virtual void WriteAttribute(
string name,
PositionTagged <string> prefix,
PositionTagged <string> suffix,
params AttributeValue[] values)
{
if (prefix == null)
{
throw new ArgumentNullException(nameof(prefix));
}
if (suffix == null)
{
throw new ArgumentNullException(nameof(suffix));
}
WriteAttributeTo(Output, name, prefix, suffix, values);
}
private void WritePositionTaggedLiteral(TextWriter writer, PositionTagged <string> value)
{
WritePositionTaggedLiteral(writer, value.Value, value.Position);
}
public virtual void WriteAttributeTo(TextWriter writer,
string name,
PositionTagged <string> prefix,
PositionTagged <string> suffix,
params AttributeValue[] values)
{
var first = true;
var wroteSomething = false;
if (values.Length == 0)
{
// Explicitly empty attribute, so write the prefix and suffix
WritePositionTaggedLiteral(writer, prefix);
WritePositionTaggedLiteral(writer, suffix);
}
else
{
for (var i = 0; i < values.Length; i++)
{
var attrVal = values[i];
var val = attrVal.Value;
var next = i == values.Length - 1 ?
suffix : // End of the list, grab the suffix
values[i + 1].Prefix; // Still in the list, grab the next prefix
if (val.Value == null)
{
// Nothing to write
continue;
}
// The special cases here are that the value we're writing might already be a string, or that the
// value might be a bool. If the value is the bool 'true' we want to write the attribute name
// instead of the string 'true'. If the value is the bool 'false' we don't want to write anything.
// Otherwise the value is another object (perhaps an HtmlString) and we'll ask it to format itself.
string stringValue;
var boolValue = val.Value as bool?;
if (boolValue == true)
{
stringValue = name;
}
else if (boolValue == false)
{
continue;
}
else
{
stringValue = val.Value as string;
}
if (first)
{
WritePositionTaggedLiteral(writer, prefix);
first = false;
}
else
{
WritePositionTaggedLiteral(writer, attrVal.Prefix);
}
// Calculate length of the source span by the position of the next value (or suffix)
var sourceLength = next.Position - attrVal.Value.Position;
if (attrVal.Literal)
{
WriteLiteralTo(writer, stringValue ?? val.Value);
}
else
{
WriteTo(writer, stringValue ?? val.Value); // Write value
}
wroteSomething = true;
}
if (wroteSomething)
{
WritePositionTaggedLiteral(writer, suffix);
}
}
}
public virtual void WriteAttributeTo(
[NotNull] TextWriter writer,
string name,
[NotNull] PositionTagged <string> prefix,
[NotNull] PositionTagged <string> suffix,
params AttributeValue[] values)
{
var first = true;
var wroteSomething = false;
if (values.Length == 0)
{
// Explicitly empty attribute, so write the prefix and suffix
WritePositionTaggedLiteral(writer, prefix);
WritePositionTaggedLiteral(writer, suffix);
}
else
{
for (var i = 0; i < values.Length; i++)
{
var attrVal = values[i];
var val = attrVal.Value;
var next = i == values.Length - 1 ?
suffix : // End of the list, grab the suffix
values[i + 1].Prefix; // Still in the list, grab the next prefix
if (val.Value == null)
{
// Nothing to write
continue;
}
// The special cases here are that the value we're writing might already be a string, or that the
// value might be a bool. If the value is the bool 'true' we want to write the attribute name
// instead of the string 'true'. If the value is the bool 'false' we don't want to write anything.
// Otherwise the value is another object (perhaps an HtmlString) and we'll ask it to format itself.
string stringValue;
// Intentionally using is+cast here for performance reasons. This is more performant than as+bool?
// because of boxing.
if (val.Value is bool)
{
if ((bool)val.Value)
{
stringValue = name;
}
else
{
continue;
}
}
else
{
stringValue = val.Value as string;
}
if (first)
{
WritePositionTaggedLiteral(writer, prefix);
first = false;
}
else
{
WritePositionTaggedLiteral(writer, attrVal.Prefix);
}
// Calculate length of the source span by the position of the next value (or suffix)
var sourceLength = next.Position - attrVal.Value.Position;
BeginContext(attrVal.Value.Position, sourceLength, isLiteral: attrVal.Literal);
// The extra branching here is to ensure that we call the Write*To(string) overload where
// possible.
if (attrVal.Literal && stringValue != null)
{
WriteLiteralTo(writer, stringValue);
}
else if (attrVal.Literal)
{
WriteLiteralTo(writer, val.Value);
}
else if (stringValue != null)
{
WriteTo(writer, stringValue);
}
else
{
WriteTo(writer, val.Value);
}
EndContext();
wroteSomething = true;
}
if (wroteSomething)
{
WritePositionTaggedLiteral(writer, suffix);
}
}
}
public AttributeValue(PositionTagged <string> prefix, PositionTagged <object> value, bool literal)
{
Prefix = prefix;
Value = value;
Literal = literal;
}
public virtual void WriteAttributeTo(
[NotNull] TextWriter writer,
string name,
[NotNull] PositionTagged <string> prefix,
[NotNull] PositionTagged <string> suffix,
params AttributeValue[] values)
{
if (values.Length == 0)
{
// Explicitly empty attribute, so write the prefix
WritePositionTaggedLiteral(writer, prefix);
}
else if (IsSingleBoolFalseOrNullValue(values))
{
// Value is either null or the bool 'false' with no prefix; don't render the attribute.
return;
}
else if (UseAttributeNameAsValue(values))
{
var attributeValue = values[0];
var positionTaggedAttributeValue = attributeValue.Value;
WritePositionTaggedLiteral(writer, prefix);
var sourceLength = suffix.Position - positionTaggedAttributeValue.Position;
var nameAttributeValue = new AttributeValue(
attributeValue.Prefix,
new PositionTagged <object>(name, attributeValue.Value.Position),
literal: attributeValue.Literal);
// The value is just the bool 'true', write the attribute name instead of the string 'True'.
WriteAttributeValue(writer, nameAttributeValue, sourceLength);
}
else
{
// This block handles two cases.
// 1. Single value with prefix.
// 2. Multiple values with or without prefix.
WritePositionTaggedLiteral(writer, prefix);
for (var i = 0; i < values.Length; i++)
{
var attributeValue = values[i];
var positionTaggedAttributeValue = attributeValue.Value;
if (positionTaggedAttributeValue.Value == null)
{
// Nothing to write
continue;
}
var next = i == values.Length - 1 ?
suffix : // End of the list, grab the suffix
values[i + 1].Prefix; // Still in the list, grab the next prefix
// Calculate length of the source span by the position of the next value (or suffix)
var sourceLength = next.Position - attributeValue.Value.Position;
WriteAttributeValue(writer, attributeValue, sourceLength);
}
}
WritePositionTaggedLiteral(writer, suffix);
}