1、按“ALT+F11”两个按键，弹出VBA模式
右击Thisworkbook-插入-模块
2、拷贝下面代码到空白处，然后关闭VBA
Function week2Day(y As Integer, i As Integer, k As Integer) As String
Dim datetemp As Date, j As Integer
If i > 52 Then
MsgBox ("一年最多只有52个周！")
weekFristDay = "1900-1-1"
Exit Function
End If
datetemp = y & "-" & 1 & "-" & 1
j = VBA.Weekday(datetemp, vbMonday)
j = (8 - j) + (i - 2) * 7
datetemp = DateAdd("d", j + k - 1, datetemp)
week2Day = CStr(datetemp)
End Function
3、在空单元格中输入下面函数
=week2day(2014,1,5) ‘其中第一个参数是年，第二个参数是第几周，第三个参数该周第几天，该函数返回为2014-1-3日
