#include "keyhighlight.h"
#include<QFont>
#include <QColor>
Keyhighlight::Keyhighlight(QTextDocument *parent)
:QSyntaxHighlighter(parent)
{
setNormalFormat();//高亮的设置会依次覆盖　因此越后面的设置优先值越高
setDigitalFormat();
setFuncFormat();
setKeywordFormat();
setStringFormat();
setCommentFormat();
}void Keyhighlight::setNormalFormat()
{
HighlightRule nmrule;//普通文本高亮规则 结构体= pattern + format
QFont nmF("Courier");//字体设置
normalFormat.setFont(nmF);//普通文本格式设置
nmrule.pattern = QRegExp(".+");//正则表达式匹配除\n的所有字符
nmrule.format = normalFormat;
highlightRules.append(nmrule);
}
void Keyhighlight::setDigitalFormat()//数字
{
HighlightRule dgrule;
QFont dgtF("Courier");
digitalFormat.setFont(dgtF);
digitalFormat.setForeground(QColor(128,0,128));//设置颜色为紫色
dgrule.pattern = QRegExp("[0-9]+");//0-9数字正则匹配
dgrule.format = digitalFormat;
highlightRules.append(dgrule);
}
void Keyhighlight::setFuncFormat()//函数名
{
HighlightRule funrule;
QFont funF("Courier");
functionFormat.setFont(funF);
functionFormat.setForeground(QColor(0,255,0));//设置颜色为绿色
funrule.pattern = QRegExp("\\b[A-Za-z0-9_]+(?=\\()");//正则匹配()前的标识符　即函数名
funrule.format = functionFormat;
highlightRules.append(funrule);
}
void Keyhighlight::setKeywordFormat()//关键字的正则匹配
{
HighlightRule keyrule;
QFont keyF("Courier");
keywordFormat.setFont(keyF);
keywordFormat.setForeground(QColor(0,191,255));//蓝色
QStringList keywordPatterns;
keywordPatterns << "\\bchar\\b" << "\\bclass\\b" <<
"\\bdouble\\b"
<< "\\benum\\b" << "\\bexplicit\\b"<<
"\\bint\\b"
<< "\\blong\\b" << "\\bshort\\b" << "\\bstruct\\b"
<< "\\btypedef\\b" << "\\btypename\\b"<< "\\bunion\\b"
<< "\\bunsigned\\b" << "\\bvoid\\b"<< "\\bauto\\b"<<"\\btemplate\\b";//数据类型关键字
foreach (const QString &pattern, keywordPatterns)
{
keyrule.pattern = QRegExp(pattern);
keyrule.format = keywordFormat;
highlightRules.append(keyrule);
}
HighlightRule key2rule;
QFont key2F("Courier");
keywordFormat_two.setFont(key2F);
keywordFormat_two.setForeground(QColor(255,0,0));//红色
QStringList keywordPatterns2;
keywordPatterns2 <<"\\bfor\\b"<<"\\bif\\b"<<"\\belse\\b"<<"\\bwhile\\b"
<<"\\bbreak\\b"
<<"\\bcontinue\\b"<<"\\bgoto\\b"<<"\\bswitch\\b"<<"\\
bcase\\b"
<<"\\bdefault\\b"<<"\\breturn\\b"<<"\\bconst\\b"<<"\\
bstatic\\b"
<<"\\bextern\\b"<<"\\bregister\\b"<<"\\bsizeof\\b"<<"

//正则匹配两个引号或三角括号之间的字符串
strrule.format = stringFormat;
highlightRules.append(strrule);
}
void Keyhighlight::setCommentFormat()//注释
{
HighlightRule cmtrule;
singleLineCommentFormat.setForeground(QColor(192,192,192));

//灰色
cmtrule.pattern = QRegExp("//[^\n]*");
cmtrule.format = singleLineCommentFormat;
highlightRules.append(cmtrule);
multiLineCommentFormat.setForeground(QColor(192,192,192));
commentStartExpression = QRegExp("/\\*");

//多行注释正则匹配开始字符
commentEndExpression = QRegExp("\\*/");//结束字符
}void Keyhighlight::highlightBlock(const QString &text)//text是单行传入的
{
foreach(const HighlightRule & rule,highlightRules)
{
QRegExp expression(rule.pattern);
int index = expression.indexIn(text);
while(index >= 0)
{
int length = expression.matchedLength();
setFormat(index,length,rule.format);
index = expression.indexIn(text,index+length);
}
}
setCurrentBlockState(0);
int startIndex = 0;
if (previousBlockState() != 1)
startIndex = commentStartExpression.indexIn(text);
while (startIndex >= 0)
{
int endIndex = commentEndExpression.indexIn(text, startIndex);
int commentLength;
if (endIndex == -1)
{
setCurrentBlockState(1);
commentLength = text.length() - startIndex;
}
else
{
commentLength = endIndex - startIndex + commentEndExpression.matchedLength();
}
setFormat(startIndex, commentLength, multiLineCommentFormat);
startIndex = commentStartExpression.indexIn(text, startIndex + commentLength);
}
}