moveFirst 方法
更新:2007 年 11 月
將目前的項目重設為 Enumerator 物件中的第一項。
function moveFirst()
備註
如果集合物件中沒有任何項目的話,目前的項目會設成 undefined。
範例
在以下範例中,使用 moveFirst 方法來從清單開始處評估 Drives 集合物件的成員:
function ShowFirstAvailableDrive(){
var fso, s, e, x; //Declare variables.
fso = new ActiveXObject("Scripting.FileSystemObject");
e = new Enumerator(fso.Drives); //Create Enumerator object.
e.moveFirst(); //Move to first drive.
s = ""; //Initialize s.
do
{
x = e.item(); //Test for existence of drive.
if (x.IsReady) //See if it's ready.
{
s = x.DriveLetter + ":"; //Assign 1<SUP>st</SUP> drive letter to s.
break;
}
else
if (e.atEnd()) //See if at the end of the collection.
{
s = "No drives are available";
break;
}
e.moveNext(); //Move to the next drive.
}
while (!e.atEnd()); //Do while not at collection end.
return(s); //Return list of available drives.
}