mysyntaxhighlighter.cpp

#include "mysyntaxhighlighter.h"
#include "label.h"
#include "QDebug"
MySyntaxHighlighter::MySyntaxHighlighter(QString str1,QTextDocument *parent) :
    QSyntaxHighlighter(parent)
{
    str = str1;
}

void MySyntaxHighlighter::highlightBlock(const QString &text) //高亮文本块
{
    QTextCharFormat myFormat; //字符格式
    myFormat.setFontWeight(QFont::Bold);
    myFormat.setForeground(Qt::red);

    QString pattern = "\\b"+str+"\\b"; //要匹配的字符，这里是“char”单词

    QRegExp expression(pattern); //创建正则表达式
    expression.setCaseSensitivity(Qt::CaseInsensitive);
    int index = text.indexOf(expression); //从位置0开始匹配字符串
    //如果匹配成功，那么返回值为字符串的起始位置，它大于或等于0
    while (index >= 0)
    {
        int length = expression.matchedLength(); //要匹配字符串的长度
        setFormat(index, length, myFormat); //对要匹配的字符串设置格式
        index = text.indexOf(expression, index + length);
        //从前面匹配到的字符串之后继续匹配
     }
}