​x
 
<!DOCTYPE html>
<html>
<body>
​
<p>请单击按钮，在字符串中每行的开头对“is”进行多行搜索。</p>
​
<button onclick="myFunction()">试一试</button>
​
<p id="demo"></p>
​
<script>
function myFunction() {
  var str = "\nIs th\nis it?";
  var patt1 = /^is/m;
  var result = str.match(patt1);
  document.getElementById("demo").innerHTML = result;
}
</script>
​
</body>
</html>
​