看了Demo中文本高亮显示的例子，看到多行注释的时候就看不懂了，主要是两个函数
int QSyntaxHighlighter::previousBlockState () const [protected]
Returns the end state of the text block previous to the syntax highlighter's current block. If no value was previously set, the returned value is -1.
int QSyntaxHighlighter::currentBlockState () const [protected]
Returns the state of the current text block. If no value is set, the returned value is -1.
我想知道这两个函数是怎么个意思？返回前一个文本块的状态和当前文本块的状态？谁能解释一下哈！还有文本块是啥意思！
