<html><body><p>单击该按钮可对字符串中的字符“i”和“s”进行全局搜索。</p><button onclick="myFunction()">试一试</button><p id="demo"></p><script>function myFunction() { var str = "Do you know if this is all there is?"; var patt1 = /[is]/gi; var result = str.match(patt1); document.getElementById("demo").innerHTML = result;}</script></body></html>