---- 一． 概述

---- 幾乎所有數(shù)據(jù)庫應(yīng)用軟件，都需要打印單證和報(bào)表。常見的方法是利用VB的Crystal Reports(水晶報(bào)表)方式，通過TextBox等數(shù)據(jù)綁定控件，調(diào)用Print方法直接輸出。雖然Crystal Report這一個(gè)功能強(qiáng)大、樣式豐富且無編程方式的報(bào)表編制程序能適應(yīng)大部分單證、報(bào)表打印的需要，但是Crystal Reports引擎是一個(gè)動態(tài)鏈接庫，需許多文件支持和調(diào)用更多系統(tǒng)資源，大大增加系統(tǒng)負(fù)擔(dān)。

---- 另一種解決辦法是通過Printer對象的Print方法，直接打印字符串。這雖然減少了系統(tǒng)資源的開銷，但它不能直接用于打印復(fù)雜的單證和報(bào)表。本文通過兩個(gè)實(shí)例，闡述一個(gè)通用折行打印程序的編程和在單證及報(bào)表的應(yīng)用。

---- 二． 編程實(shí)現(xiàn)及實(shí)例

---- 為便于闡述的方便，我們先建立一個(gè)Access數(shù)據(jù)庫Standards.mdb，其內(nèi)SN表由以下幾個(gè)字段組成：

---- 標(biāo)準(zhǔn)號（文本，17）

---- 標(biāo)準(zhǔn)名稱（文本，255）

---- 英文名稱（文本，255）

---- 實(shí)施日期（日期，8）

---- 修定日期（日期，8）

---- 發(fā)布日期（日期，8）

---- 代替標(biāo)準(zhǔn)（文本，50）

---- 通用折行打印程序編制操作如下：

---- 1.在VB5.0編程環(huán)境中，新建一個(gè)工程Project1；

---- 2. 在Project1中添加Moduel，在Moduel模塊中定義一個(gè)記錄最大折行數(shù)的公用變量Rowlab和Function函數(shù)（以下程序都經(jīng)過實(shí)際運(yùn)行測試，可以原樣復(fù)制使用）；

Public rowlab As Integer       
'定義一個(gè)公用變量
Function prnt11(X As Integer, Y As
Integer,Font As Single, Txt As String, Val As Integer)
Dim str As String, str1 As String,
str2 As String ,i As Integer
Printer.CurrentX = X
Printer.CurrentY = Y
Printer.FontBold = False
Printer.FontSize = font
str = txt
str2 = str
i = 0
rowlab = 0
If Len(Trim(str)) = 0 Then
     rowlab = 1   '待打印字符串為空的標(biāo)志
Else
  Do While Len(str) > 0
     Printer.CurrentX = X
     Printer.CurrentY = Y + rowlab * 240
     rowlab = rowlab + 1
     If Len(str) >= val Then
        str1 = Mid(str, 1, val)
        Printer.Print str1
        i = i + 1
        str = Mid(str2, i * val + 1)
     Else
       Printer.Print str
       Exit Do
     End If
   Loop
End If
End Function

---- 3． 在Project1中新建一個(gè)窗體Form1，窗體上添加一個(gè)Data控件Data1，一個(gè)MSFlexGrid控件MSFGrid1，7個(gè) TextBox和兩個(gè)命令按鈕CmdPrnt1、CmdPrnt2。設(shè)置Data控件的屬性：

.. DatabaseName="Standards.mdb"
..RecordSourse="SN"
   MSFGrid1屬性：
       .DataSource="Data1"
   Text1屬性：
       .DataSource="Data1"
       .DataField="標(biāo)準(zhǔn)號"
   Text2~Text7類同。

---- CmdPrnt1、CmdPrnt2分別為打印單條記錄和多條記錄的按鈕。

---- 實(shí)例1：文字串定位折行打印在口岸聯(lián)檢部門中應(yīng)用非常廣泛。下述例子是用CmdPrnt1的Click事件代碼實(shí)現(xiàn)了對文字串定位折行打�。�

Private Sub CmdPrnt1_Click()
Dim str As String, str1 As String ,txt As String
Dim strx As Integer, stry As Integer,i As Integer
strx = 200
stry = 0
txt = Space(20) + "中國出入境檢驗(yàn)檢疫標(biāo)準(zhǔn)目錄檢索STEMS 2000"
Printer.FontName = "黑體"
dd = prnt11(strx, stry, 10, txt, 50)
stry = stry + rowlab * 240
Printer.Line (0, stry)-(9000, stry)
Printer.FontName = "宋體"
txt = "標(biāo)準(zhǔn)號：" + Space(2) + Trim(Text1) + Space(3) +
"發(fā)布日期：" + Trim(Text4) + Space(3) + "實(shí)施日期："
+ Trim(Text6) + Space(3) + "修定日期：" + Trim(Text5) '+ Chr(13)
stry = stry + 240
dd = prnt11(strx, stry, 10, txt, 70)
stry = stry + rowlab * 240
txt = "代替標(biāo)準(zhǔn)："
dd = prnt11(strx, stry, 10, txt, 10)
dd = prnt11(strx + 1000, stry, 10, Trim(Text7), 60)
stry = stry + rowlab * 240
txt = "標(biāo)準(zhǔn)名稱："
dd = prnt11(strx, stry, 10, txt, 10)
dd = prnt11(strx + 1000, stry, 10, Trim(Text4), 38)
stry = stry + rowlab * 240
txt = "英文名稱："
dd = prnt11(strx, stry, 10, txt, 10)
dd = prnt11(strx + 1000, stry, 10, Text5, 72)
Printer.EndDoc
End Sub

---- 注： Prnt11函數(shù)原形：prnt11(X As Integer, Y As Integer, Font As Single, Txt As String, Val As Integer)，其各參數(shù)含義如下：

---- X、Y為待打印字符串左上角起始座標(biāo)；

---- Font為字體大��；

---- Txt為待打印字符串；

---- Val為字符串打印折行長度。

---- 實(shí)例2：直接打印表格式窗體顯示的多記錄多字段，往往因某些字段的字節(jié)太多而造成紙張寬度不足。以下 CmdPrnt2的Click事件中的代碼，實(shí)現(xiàn)了對上述MSFGrid1表格記錄的打印：

Private Sub CmdPrnt2_Click()
Dim fnt As Single
Dim pp As Integer
Dim stry As Integer, strx As Integer
Dim stry1 As Integer,
strx1 As Integer, linw As Integer
Dim page1 As Integer, p As Integer,
gridrow As Integer, ii As Integer
p = 0
ii = 1  'ii記錄MSFGRID1表格同一記錄內(nèi)字段最大打印行
pp = 0 '開始頁碼
ss$ = "中國出入境檢驗(yàn)檢疫標(biāo)準(zhǔn)目錄檢索STEMS 2000" ' 表頭
Static a(4) As Integer
kan = 0
a(2) = 1680
a(3) = 2800
a(4) = 5300
page1 = 46 '定義每頁行數(shù)
  strx = 200
  strx1 = 200
  stry = 1400
  stry1 = 1400
  linw = 240 '定義行寬
  fnt = 10 '定義字體大小
  For i = 2 To 4
      kan = kan + a(i)
  Next
  gridrow = Datdatact1.Recordset.RecordCount
  If gridrow = 0 Then
     MsgBox "無滿足條件記錄打�。�"
     Exit Sub
End If
  Printer.FontName = "黑體"
  dd = prnt11(3300, 700, fnt, ss$, 26) '打印標(biāo)題
  dd = prnt11(500, stry - 250, fnt, "標(biāo)準(zhǔn)號", 26)
  dd = prnt11(2690, stry - 250, fnt, "標(biāo)準(zhǔn)名稱", 26)
  dd = prnt11(6690, stry - 250, fnt, "英文名稱", 26)
  Printer.Line (strx - 20, stry - 30)-(10460, stry - 30)
  Printer.FontName = "宋體"
  For j = 1 To gridrow  '打印gridrow條記錄
       MSFGrid1.Row = j
       strx = strx1
       For i = 2 To 4 '假設(shè)只打印2-3 列
         MSFGrid1.Col = i
         dd = prnt11(strx, stry, fnt,
MSFGrid1.Text, IIf(i = 3, 13, 55))
         If ii < rowlab Then
'ii記錄同一記錄內(nèi)字段最大打印行
           ii = rowlab
         End If
         strx = strx + a(i)
       Next
       p = p + ii
       rowlab = ii
       ii = 1 '重新初始化
       If p > page1 Then
           p = 0
           strx = strx1
           For n = 2 To 4
             strx = strx + a(n)
           Next
           pp = pp + 1
           stry = stry + rowlab * linw
           foot$ = "第" + CStr(pp) + "頁"
           dd = prnt11(strx / 2, stry + 3 * linw, 10, foot$, 26)
           stry = stry1
           Printer.NewPage
           Printer.FontName = "黑體"
           dd = prnt11(3300, 700, fnt, ss$, 26)
           dd = prnt11(500, stry - 250, fnt, "標(biāo)準(zhǔn)號", 26)
           dd = prnt11(2690, stry - 250, fnt, "標(biāo)準(zhǔn)名稱", 26)
           dd = prnt11(6690, stry - 250, fnt, "英文名稱", 26)
           Printer.Line (-20, stry - 30)-(10460, stry - 30)
           '打印起始線
           Printer.FontName = "宋體"
           strx = strx1
         Else
           stry = stry + rowlab * linw
         End If
      Next
      If p < page1 Then
          For p = 0 To page1 + 1
             strx = strx1
          Next
      End If
      strx = strx1
      For n = 2 To 4
          strx = strx + a(n)
      Next
      pp = pp + 1
      foot$ = "第" + CStr(pp) + "頁"
      dd = prnt11(strx / 2, stry + 3 * linw, 10, foot$, 26)
      Printer.EndDoc
  End Sub

---- 以上程序在簡體中文Windows98、VB5.0環(huán)境中調(diào)試通過。 　
  資料來源：孔祥軍 蘇悅娟