Javascript function : substring()

Javascript function : substring()

有時候功能太多也是個問題,
每次用到都有些迷惑:

經測試:
alert('ABCDEFGH'.substring(3,1)); = 'BC'
alert('ABCDEFGH'.substring(2,4)); = 'CD'
alert('ABCDEFGH'.substring(5,2)); = 'CDE'
alert('ABCDEFGH'.substring(1,3)); = 'BC'
alert('ABCDEFGH'.substring(4,2)); = 'CD'
alert('ABCDEFGH'.substring(2,5)); = 'CDE'

結論是:
substring(3,1) = substring(1,3)
從小數字(0開始)到大數字(1開始)止

01234567(小)
ABCDEFGH
12345678(大)

好天才的設計師, 弄出這種指令!!