NPOI方法总结 VB 1.4.1版本（预用版本）

我们看看这里有很多块， 有台头标题的处理和   逐行添加的处理，   再者就是求和的处理。

多运行一下这些代码

1. 台头标题的处理， 看这里就有多表头的处理， 本人就对3行表头和2行表头的1行表头提供了支持。

  1             Dim HeadRow As NPOI.SS.UserModel.Row
  2             Dim HeadCell As Cell = Nothing
  3             Dim cl As Integer = p_dt.Columns.Count
  4             p_HeaderRow = If(p_HeaderRow <= 0 OrElse p_HeaderRow > 3, 1, p_HeaderRow)
  5             For l As Integer = 1 To p_HeaderRow
  6                 HeadRow = npoiSheet.CreateRow(p_StartRow)
  7                 p_StartRow += 1
  8                 For i = p_StartColumn To cl + (p_StartColumn - 1)
  9                     HeadCell = HeadRow.CreateCell(i)
 10                     Dim car1 As Char() = New Char() {"|"}
 11                     '取值符号
 12                     Dim titleArray As String() = p_dt.Columns(i - p_StartColumn).Caption.ToString().Split(car1)
 13 
 14                     If p_HeaderRow = 3 Then
 15                         ' 3行 表头
 16                         If titleArray.Length = 3 Then
 17                             If l = 1 Then
 18                                 HeadCell.CellStyle = cellstyleHeader
 19                             Else
 20                                 HeadCell.SetCellValue(titleArray(l - 1))
 21                                 HeadCell.CellStyle = cellstyleHeader
 22                             End If
 23                         ElseIf titleArray.Length = 2 Then
 24                             If l = 2 Then
 25                                 HeadCell.CellStyle = cellstyleHeader
 26                                 HeadCell.SetCellValue(titleArray(0))
 27                             ElseIf l = 3 Then
 28                                 HeadCell.CellStyle = cellstyleHeader
 29                                 HeadCell.SetCellValue(titleArray(1))
 30                             ElseIf l = 1 Then
 31                                 HeadCell.CellStyle = cellstyleHeader
 32                             End If
 33                         ElseIf titleArray.Length = 1 Then
 34                             If 3 = l Then
 35                                 HeadCell.SetCellValue(titleArray(0))
 36                                 HeadCell.CellStyle = cellstyleHeader
 37                             End If
 38                             If l = 1 Then
 39                                 HeadCell.CellStyle = cellstyleHeader
 40                             End If
 41                         Else
 42                         End If
 43                     ElseIf p_HeaderRow = 2 Then
 44                         ' 2行 表头 
 45                         If titleArray.Length = 2 Then
 46                             If l = 1 Then
 47                                 HeadCell.CellStyle = cellstyleHeader
 48                                 HeadCell.SetCellValue(titleArray(l - 1))
 49                             Else
 50                                 HeadCell.CellStyle = cellstyleHeader
 51                                 HeadCell.SetCellValue(titleArray(l - 1))
 52                             End If
 53                         ElseIf titleArray.Length = 1 Then
 54                             If 2 = l Then
 55                                 HeadCell.SetCellValue(titleArray(0))
 56                                 HeadCell.CellStyle = cellstyleHeader
 57                             End If
 58                             If l = 1 Then
 59                                 HeadCell.CellStyle = cellstyleHeader
 60                             End If
 61                         Else
 62                             ' 默认 头行  + （中间和尾行）组合 
 63                             If titleArray.Length = 3 Then
 64                                 If l = 1 Then
 65                                     HeadCell.SetCellValue(titleArray(0))
 66                                     HeadCell.CellStyle = cellstyleHeader
 67                                 ElseIf l = 2 Then
 68                                     HeadCell.SetCellValue(titleArray(1) & titleArray(2))
 69                                     HeadCell.CellStyle = cellstyleHeader
 70                                 End If
 71                             ElseIf titleArray.Length = 2 Then
 72                                 If l = 1 Then
 73                                     HeadCell.CellStyle = cellstyleHeader
 74                                     HeadCell.SetCellValue(titleArray(0))
 75                                 ElseIf l = 2 Then
 76                                     HeadCell.SetCellValue(titleArray(1))
 77                                     HeadCell.CellStyle = cellstyleHeader
 78                                 End If
 79                             ElseIf titleArray.Length = 1 Then
 80                                 If 2 = l Then
 81                                     HeadCell.SetCellValue(titleArray(0))
 82                                     HeadCell.CellStyle = cellstyleHeader
 83                                 End If
 84                                 If l = 1 Then
 85                                     HeadCell.CellStyle = cellstyleHeader
 86                                 End If
 87                             Else
 88 
 89                             End If
 90                         End If
 91                     Else
 92                         ' 1行 表头
 93                         HeadCell.SetCellValue(p_dt.Columns(i - p_StartColumn).Caption.ToString().Replace("|", ""))
 94                         HeadCell.CellStyle = cellstyleHeader
 95                     End If
 96                     If i = p_StartColumn Then
 97                         HeadCell.CellStyle = cellstyleHeader
 98                     End If
 99 
100                     HeadCell = Nothing
101                 Next
102                 Dim k As Integer
103                 '合并列 前1 前2行
104                 If l <> (If(p_HeaderRow = 2, 2, (If(p_HeaderRow = 3, 3, 1)))) Then
105                     For i = p_StartColumn To cl + (p_StartColumn - 1)
106                         HeadCell = HeadRow.GetCell(i)
107                         If "" <> HeadCell.StringCellValue.ToString() AndAlso HeadCell.StringCellValue.ToString() IsNot Nothing Then
108                             Dim y As Integer = 0
109                             For k = i + 1 To cl + (p_StartColumn - 1)
110                                 Dim compareCell As Cell = Nothing
111                                 compareCell = HeadRow.GetCell(k)
112                                 If HeadCell.StringCellValue.ToString() = compareCell.StringCellValue.ToString() Then
113                                     If "" <> compareCell.StringCellValue.ToString() AndAlso compareCell.StringCellValue.ToString() IsNot Nothing Then
114                                         y = k
115                                     End If
116                                 Else
117                                     k = cl + p_StartColumn
118                                 End If
119                             Next
120                             If y <> 0 Then
121                                 npoiSheet.AddMergedRegion(New CellRangeAddress(StartRow + l - 1, StartRow + l - 1, i, y))
122                             End If
123                         End If
124                         HeadCell = Nothing
125                     Next
126                 End If
127                 HeadRow = Nothing
128             Next
129 
130             '合并空格和添加备注
131             If 1 <> p_HeaderRow Then
132                 For i = p_StartColumn To cl + (p_StartColumn - 1)
133                     For l As Integer = 0 To p_HeaderRow - 1
134                         If l <> p_HeaderRow - 1 Then
135                             HeadRow = npoiSheet.GetRow(StartRow + l)
136                             ' 0 , 1 rows
137                             HeadCell = HeadRow.GetCell(i)
138                             If "" = HeadCell.StringCellValue.ToString() OrElse HeadCell.StringCellValue.ToString() Is Nothing Then
139                                 If p_HeaderRow = 3 Then
140                                     If "" = npoiSheet.GetRow(StartRow + l + 1).GetCell(i).StringCellValue.ToString() Then
141                                         HeadCell.SetCellValue(npoiSheet.GetRow(StartRow + 2).GetCell(i).StringCellValue.ToString())
142                                         npoiSheet.AddMergedRegion(New CellRangeAddress(StartRow + l, StartRow + 2, i, i))
143                                         l = 2
144                                     Else
145                                         HeadCell.SetCellValue(npoiSheet.GetRow(StartRow + 1).GetCell(i).StringCellValue.ToString())
146                                     End If
147                                 Else
148                                     HeadCell.SetCellValue(npoiSheet.GetRow(StartRow + 1).GetCell(i).StringCellValue.ToString())
149                                     npoiSheet.AddMergedRegion(New CellRangeAddress(StartRow + l, StartRow + 1, i, i))
150                                 End If
151                             End If
152                             HeadRow = Nothing
153                             HeadCell = Nothing
154                         End If
155                     Next
156                 Next
157             End If

 2。 逐行添加的处理， 多宽度有最大的限制

 1  Dim DataRow As NPOI.SS.UserModel.Row
 2 
 3                 For Each row As DataRow In p_dt.Rows
 4                     DataRow = npoiSheet.CreateRow(p_StartRow)
 5                     p_StartRow += 1
 6                     For Each drpt As DataColumn In p_dt.Columns
 7                         cell = DataRow.CreateCell(drpt.Ordinal + p_StartColumn)
 8                         Select Case drpt.DataType.ToString()
 9                             Case "System.DateTime"
10                                 If Not row(drpt).Equals(System.DBNull.Value) AndAlso "" <> row(drpt).ToString().Trim() Then
11                                     Dim p_dtime As DateTime
12                                     DateTime.TryParse(row(drpt).ToString(), p_dtime)
13                                     cell.SetCellValue(p_dtime.ToString("yyyy-MM-dd HH:mm:ss"))
14                                 End If
15                                 cell.CellStyle = cellstyledate
16                                 Dim date1 As DateTime = DateTime.Now
17                                 Dim columnLength As Integer = System.Text.Encoding.Default.GetBytes(date1.ToString()).Length
18                                 npoiSheet.SetColumnWidth(drpt.Ordinal + p_StartColumn, (columnLength + 3) * 256)
19                                 Exit Select
20                             Case "System.Int16", "System.Int32"
21                                 Dim doubInt As Integer
22                                 If Not row(drpt).Equals(System.DBNull.Value) AndAlso "" <> row(drpt).ToString().Trim() Then
23                                     doubInt.TryParse(row(drpt).ToString(), doubInt)
24                                     cell.SetCellValue(doubInt)
25                                 End If
26 
27                                 cell.CellStyle = cellstylebody
28                                 Dim columnLength As Integer = System.Text.Encoding.Default.GetBytes(row(drpt).ToString()).Length
29                                 Dim IntcColumnWidth As Integer = IIf(npoiSheet.GetColumnWidth(drpt.Ordinal) > 3 * 256, npoiSheet.GetColumnWidth(drpt.Ordinal), 3 * 256)
30                                 If IntcColumnWidth <= (columnLength + 3) * 256 Then
31                                     npoiSheet.SetColumnWidth(drpt.Ordinal + p_StartColumn, (columnLength + 6) * 256)
32                                 End If
33                                 Exit Select
34                             Case "System.Double", "System.Decimal"
35                                 Dim doubV As Double
36                                 If Not row(drpt).Equals(System.DBNull.Value) AndAlso "" <> row(drpt).ToString().Trim() Then
37                                     Double.TryParse(row(drpt).ToString(), doubV)
38                                     cell.SetCellValue(doubV)
39                                 End If
40 
41                                 cell.CellStyle = cellstylebodyDouble
42                                 Dim columnLength As Integer = System.Text.Encoding.Default.GetBytes(row(drpt).ToString()).Length
43                                 Dim IntcColumnWidth As Integer = IIf(npoiSheet.GetColumnWidth(drpt.Ordinal) > 3 * 256, npoiSheet.GetColumnWidth(drpt.Ordinal), 3 * 256)
44                                 If IntcColumnWidth <= (columnLength + 3) * 256 Then
45                                     npoiSheet.SetColumnWidth(drpt.Ordinal + p_StartColumn, (columnLength + 6) * 256)
46                                 End If
47                                 Exit Select
48                             Case Else
49                                 cell.SetCellValue(row(drpt).ToString())
50                                 cell.CellStyle = cellstylebody
51 
52 
53                                 '最多宽度 不能超过 10个字符     
54                                 Dim columnLength As Integer = System.Text.Encoding.Default.GetBytes(row(drpt).ToString()).Length
55                                 Dim IntcColumnWidth As Integer = IIf(npoiSheet.GetColumnWidth(drpt.Ordinal) > 3 * 256, npoiSheet.GetColumnWidth(drpt.Ordinal), 3 * 256)
56                                 If IntcColumnWidth <= (columnLength + 3) * 256 Then
57                                     npoiSheet.SetColumnWidth(drpt.Ordinal + p_StartColumn, (columnLength + 3) * 256)
58                                 End If
59 
60                                 If 17 <= (columnLength + 3) AndAlso p_blAutoWF Then
61                                     npoiSheet.SetColumnWidth(drpt.Ordinal + p_StartColumn, 17 * 256)
62                                 End If
63                                 Exit Select
64                         End Select
65 
66                     Next
67                 Next

3.再者就是求和的处理， 这个就不计较的复杂了。 考虑到cpu的使用效率的 问题。 采用的是subtotal方法客户端的计算。但是宽度如何处理呢。

方法是有的需要考虑误差范围。

 1                     For Each column As DataColumn In p_dt.Columns
 2                         Dim cs As Integer = column.Ordinal + p_StartColumn
 3                         Select Case column.DataType.ToString()
 4                             '整型  
 5                             '浮点型  
 6                             Case "System.Decimal", "System.Double"
 7                                 If cs <> p_StartColumn Then
 8                                     Totalcell = TotalRow.CreateCell(cs, CellType.NUMERIC)
 9                                     letter = ""
10                                     If (cs \ 26 - 1) > -1 AndAlso (cs \ 26 - 1) < 26 Then
11                                         letter = NumberToStr((cs \ 26 - 1)) + NumberToStr(cs Mod 26)
12                                     Else
13                                         letter = NumberToStr(cs Mod 26)
14                                     End If
15 
16                                     Totalcell.CellFormula = String.Format("SUBTOTAL(9,{0}{1}:{2}{3})", letter, intStart, letter, p_StartRow)
17                                     Dim IntcColumnWidth As Integer = If(npoiSheet.GetColumnWidth(cs) > 5 * 256, npoiSheet.GetColumnWidth(cs), 5 * 256)
18                                     Dim dl As Integer = Sqrt(arr_total(column.Ordinal))
19 
20                                     If arr_zero(column.Ordinal) Then
21                                         npoiSheet.SetColumnWidth(cs, (IntcColumnWidth + dl * 256))
22                                     End If
23 
24                                 End If
25                                 Exit Select
26                             Case Else
27                                 If cs <> p_StartColumn Then
28                                     Totalcell = TotalRow.CreateCell(cs)
29                                     Totalcell.CellStyle = cellstyleSumNumLast
30                                 End If
31                                 Exit Select
32                         End Select
33                         If (Not Totalcell Is Nothing) Then
34                             Select Case column.DataType.ToString()
35                                 '浮点型  
36                                 Case "System.Decimal", "System.Double"
37                                     Totalcell.CellStyle = cellstyleSumNumLast
38                                     Exit Select
39                                 Case Else
40                                     Exit Select
41                             End Select
42                             Totalcell = Nothing
43                         End If
44 
45                     Next

方法1去excel列名

 1                     Dim letter As String
 2                     Dim NumberToStr As String() = New String(25) {}
 3                     NumberToStr(0) = "A"
 4                     NumberToStr(1) = "B"
 5                     NumberToStr(2) = "C"
 6                     NumberToStr(3) = "D"
 7                     NumberToStr(4) = "E"
 8                     NumberToStr(5) = "F"
 9                     NumberToStr(6) = "G"
10                     NumberToStr(7) = "H"
11                     NumberToStr(8) = "I"
12                     NumberToStr(9) = "J"
13                     NumberToStr(10) = "K"
14                     NumberToStr(11) = "L"
15                     NumberToStr(12) = "M"
16                     NumberToStr(13) = "N"
17                     NumberToStr(14) = "O"
18                     NumberToStr(15) = "P"
19                     NumberToStr(16) = "Q"
20                     NumberToStr(17) = "R"
21                     NumberToStr(18) = "S"
22                     NumberToStr(19) = "T"
23                     NumberToStr(20) = "U"
24                     NumberToStr(21) = "V"
25                     NumberToStr(22) = "W"
26                     NumberToStr(23) = "X"
27                     NumberToStr(24) = "Y"
28                     NumberToStr(25) = "Z"

 

方法2去计算宽度

 1                     Dim arr_total As Integer() = New Integer(p_dt.Columns.Count - 1) {}
 2                     Dim arr_zero As Boolean() = New Boolean(p_dt.Columns.Count - 1) {}
 3 
 4                     For Each column As DataColumn In p_dt.Columns
 5                         ' column
 6                         Select Case column.DataType.ToString()
 7                             '整型  
 8                             '浮点型  
 9                             Case "System.Decimal", "System.Double"
10                                 Dim rc As Integer = p_dt.Rows.Count
11                                 Dim arrNum As Integer() = New Integer(rc - 1) {}
12                                 Dim ten As Integer = 0
13                                 For j = 0 To rc - 1
14                                     ' row
15                                     arrNum(j) = p_dt.Rows(j)(column.Ordinal).ToString().Length
16                                     If Not p_dt.Rows(j)(column.Ordinal).Equals(System.DBNull.Value) Then
17 
18                                         Dim doubV As Double = 0
19                                         If Double.TryParse(p_dt.Rows(j)(column.Ordinal).ToString(), doubV) Then
20                                             If doubV > 0 Then
21                                                 arr_zero(column.Ordinal) = True
22                                             End If
23                                         End If
24 
25                                     End If
26 
27                                 Next
28 
29 
30                                 Dim list As New ArrayList(arrNum)
31                                 list.Sort()
32                                 If list.Count > 0 Then
33                                     If Not list(list.Count - 1).Equals(System.DBNull.Value) Then
34                                         Dim max As Integer
35                                         Dim intv As Integer = 0
36                                         If Integer.TryParse(list(list.Count - 1), intv) Then
37                                             max = Convert.ToInt32(list(list.Count - 1))
38                                         End If
39 
40                                         For j = (rc - 1) To 0 Step -1
41                                             ' row
42                                             Dim min As Integer
43                                             If Not list(j).Equals(System.DBNull.Value) Then
44                                                 If Integer.TryParse(list(j), min) Then
45 
46                                                     If Convert.ToInt32(list(j)) = max Then
47                                                         ten += 1
48                                                     Else
49                                                         j = -1
50                                                     End If
51                                                     arr_total(column.Ordinal) = ten
52                                                 End If
53                                             End If
54                                         Next
55 
56                                     End If
57                                 End If
58 
59 
60                                 Exit Select
61                             Case Else
62                                 arr_total(column.Ordinal) = 0
63                                 Exit Select
64                         End Select
65                     Next
66 
67 
68 
69         Private Function Sqrt(ByVal d As Integer) As Integer
70             Dim temp As Integer = 10
71             Dim l As Integer = 0
72             While d > temp
73                 temp *= 10
74                 l += 1
75             End While
76             l += 4
77             '误差范围
78             Return l
79         End Function

 这个有什么不懂可以联系本人 QQ：1839467491