最终效果

如果单元格输入=getpychar(E2)，并下拉填充，获取的是大写首字母

1. 打开【开发工具】菜单，点击第一个【Visual
   Basic】,弹出代码窗口，在窗口左侧空白处，点击右键，选择【插入】->【模块】。窗口右侧出现一个白色背景框。
2. 复制粘贴如下代码内容到编辑框中，并保存

Function getpychar(char)

    tmp = 65536 + Asc(char)

    If (tmp >= 45217 And tmp <= 45252) Then

    getpychar = "A"

    ElseIf (tmp >= 45253 And tmp <= 45760) Then

    getpychar = "B"

    ElseIf (tmp >= 45761 And tmp <= 46317) Then

    getpychar = "C"

    ElseIf (tmp >= 46318 And tmp <= 46825) Then

    getpychar = "D"

    ElseIf (tmp >= 46826 And tmp <= 47009) Then

    getpychar = "E"

    ElseIf (tmp >= 47010 And tmp <= 47296) Then

    getpychar = "F"

    ElseIf (tmp >= 47297 And tmp <= 47613) Then

    getpychar = "G"

    ElseIf (tmp >= 47614 And tmp <= 48118) Then

    getpychar = "H"

    ElseIf (tmp >= 48119 And tmp <= 49061) Then

    getpychar = "J"

    ElseIf (tmp >= 49062 And tmp <= 49323) Then

    getpychar = "K"

    ElseIf (tmp >= 49324 And tmp <= 49895) Then

    getpychar = "L"

    ElseIf (tmp >= 49896 And tmp <= 50370) Then

    getpychar = "M"

    ElseIf (tmp >= 50371 And tmp <= 50613) Then

    getpychar = "N"

    ElseIf (tmp >= 50614 And tmp <= 50621) Then

    getpychar = "O"

    ElseIf (tmp >= 50622 And tmp <= 50905) Then

    getpychar = "P"

    ElseIf (tmp >= 50906 And tmp <= 51386) Then

    getpychar = "Q"

    ElseIf (tmp >= 51387 And tmp <= 51445) Then

    getpychar = "R"

    ElseIf (tmp >= 51446 And tmp <= 52217) Then

    getpychar = "S"

    ElseIf (tmp >= 52218 And tmp <= 52697) Then

    getpychar = "T"

    ElseIf (tmp >= 52698 And tmp <= 52979) Then

    getpychar = "W"

    ElseIf (tmp >= 52980 And tmp <= 53640) Then

    getpychar = "X"

    ElseIf (tmp >= 53679 And tmp <= 54480) Then

    getpychar = "Y"

    ElseIf (tmp >= 54481 And tmp <= 62289) Then

    getpychar = "Z"

    Else '如果不是中文，则不处理

    getpychar = char

    End If

End Function
'逐个取ASC码

Function getpy(str)

    For i = 1 To Len(str)

        getpy = getpy & getpychar(Mid(str, i, 1))

    Next i

End Function

3. 点击菜单中【保存】，弹出一个提示框，点【是】，再次弹出一个提示框，点【确定】。
4. 回到excel文件，像使用其他函数一样，单元格中输入=函数名称（单元格）回车即可
5. getpychar函数为只获取大写首字母，getpy为获取全拼大写首字母