javascript (break and lable)

<scrīpt language="javascrīpt">

outerloop:
  for(var i = 0; i < 10; i++) {
    innerloop:
      for(var j = 0; j < 10; j++) {
          if (j > 3) break;             // Quit the innermost loop
          if (i == 2) break innerloop;  // Do the same thing
          if (i == 4) break outerloop;  // Quit the outer loop
          document.write("i = " + i + " j = " + j + "<br>");
      }
  }
  document.write("FINAL i = " + i + " j = " + j + "<br>");

</scrīpt>

不带lable的break:退出所在循环的最内层循环
带lable的break:退出循环至lable处

如上代码结果为:
i = 0 j = 0
i = 0 j = 1
i = 0 j = 2
i = 0 j = 3
i = 1 j = 0
i = 1 j = 1
i = 1 j = 2
i = 1 j = 3
i = 3 j = 0
i = 3 j = 1
i = 3 j = 2
i = 3 j = 3
FINAL i = 4 j = 0