在imacros

Question

我想运行带有提示符而不是硬编码网址的网址的iMacros。我已经尝试过这段代码，但总是失败并出现错误：

http://__undefined__/

我的宏：

var macro;
macro =  "CODE:";
var URLN = prompt("Please enter your URL: ");
var CHOICE = prompt("Please enter your Choice: ");
macro +=  "VERSION BUILD=8970419 RECORDER=FX" + "\n";
macro +=  "TAB T=1" + "\n";
macro +=  "TAB CLOSEALLOTHERS" + "\n";
macro +=  "TAB T=2" + "\n";
macro +=  "URL GOTO={{!URLN}}" + "\n";
macro +=  "TAG POS=1 TYPE=BUTTON ATTR=TXT:{{!CHOICE}}" + "\n";
iimPlay(macro)

如何从提示中获取网址的任何想法？