var text = "cat,bat,sat,fat";?? //數(shù)組??var pattern1 = /.at/;??var matches = pattern1.exec(text);? //局部變量??alert(matches.index); ????//0??alert(matches[0]);?????//cat??alert(pattern1.lastIndex);???//0??matches = pattern1.exec(text);??//全局變量??alert(matches.index);??alert(matches[0]);??alert(pattern1.lastIndex);??var pattern2 = /.at/g;??? //全局變量??var matches = pattern2.exec(text);??alert(matches.index);????//0??alert(matches[0]);?????//cat??alert(pattern2.lastIndex);???//3??matches = pattern2.exec(text);??alert(matches.index);???????? //4??alert(matches[0]);???//bat??alert(pattern2.lastIndex);??//7為什么最后一個(gè)alert彈出7呢？pattern1后的全局變量與pattern2后的全局變量不是一個(gè)意思嗎？