第二個重要的類,作用是類型轉(zhuǎn)換,類名Con_Convert.在頁面代碼的開頭實例化,對象名為Convert,借用了.net的類型轉(zhuǎn)換的對象名稱.
   
   
    這個類主要解決在類型轉(zhuǎn)換時,如果直接使用類型轉(zhuǎn)換函數(shù),會因為變量為空或者格式不對而導致程序報錯,而這種報錯在大多數(shù)情況下是允許的.例如要轉(zhuǎn)換一個字符串變量為數(shù)字,如果變量為空,則一般需要自動返回0.
    另外一個重要功能就是封裝變量格式化操作,可以保持整個網(wǎng)站的輸出格式統(tǒng)一,例如時間格式,貨幣格式等等.  日期和貨幣格式化的時候,極易遇到因空值報錯的情況,一般都不得不寫個預判斷空值的邏輯,再格式化變量. 使用這個類負責類型轉(zhuǎn)換和格式化輸出后,就不用操心這些瑣碎的細節(jié)了,可以讓編程的心情得到大大改善啊.
    還有些其他格式化功能,也加了進去,例如Convert.ToPer()是用來轉(zhuǎn)換數(shù)字成百分數(shù),Convert.FirstUppercase()用來做首字母大寫...... 你可以根據(jù)自己的需要,隨時擴展這個類,不要忘記了和大家分享哦.
   
   
    有些基本的函數(shù),如果隨便寫一寫,基本可以湊合著用,但是遇到特殊情況,就要重新改寫.比如我寫的Convert.ToInt()方法,將變量轉(zhuǎn)換為Integer. 最基本的操作,是判斷一下是否為空,不為空就直接用Cint()就可以了. 但是遇到變量超出了范圍,又得判斷是否在Integer范圍內(nèi),所以又寫了一個私有方法IsOverflowInteger(),用于判斷變量值是否為某一個范圍內(nèi)的數(shù)字.經(jīng)過這樣的處理,相信基本可以處理所有的情況了.
    所以我想,Convert類中的已有方法還是會有不少需要改善的,大家如果有更好更完善的函數(shù)請發(fā)上來分享,讓它形成ASP中最標準的變量處理的類,再不用依賴ASP中那些有限的功能了.
   
   
    如下列舉一些比較主要的方法,具體細節(jié)請看代碼.
    類型判斷:
    Convert.IsInteger(ByVal Value) 判斷是否整數(shù),只允許0~9和-號
    Convert.IsInt(ByVal Value)      判斷是否int型,其下類似,不用解釋了.
    Convert.IsLng(ByVal Value) 
    Convert.IsDecimal(ByVal Value)
    Convert.IsSng(ByVal Value)
    Convert.IsDbl(ByVal Value)
    Convert.IsCur(ByVal Value)
    Convert.IsBln(ByVal Value)
    Convert.IsDat(ByVal Value)
    Convert.IsArr(ByVal Value)
   
    類型轉(zhuǎn)換:
    Convert.ToStr(ByVal Value)
    Convert.ToInt(ByVal Value)
    Convert.ToLng(ByVal Value)
    Convert.ToSng(ByVal Value)
    Convert.ToDbl(ByVal Value)
    Convert.ToBln(ByVal Value)
    Convert.ToCur(ByVal Value)
    Convert.ToDat(ByVal Value)
   
   
    格式化:
    Convert.FormatDat(ByVal Value, ByVal vStyle)        日期格式化
    Convert.FormatCur(ByVal Value,ByVal vDecimal)       貨幣格式化
    Convert.FormatNum(ByVal Value,ByVal vDecimal)       數(shù)字格式化
   
   
    其他格式化:
    Convert.ToPer(Byval value,Byval value0)             百分數(shù),帶%
    Convert.FirstUppercase(ByVal value)                 首字母大寫
    Convert.SafeSql(ByVal value)                        替換sql中的'為''
   
   
   
    代碼如下: (我不會插入代碼,不知道CSDN是怎么操作的,點插入代碼就是一個<textarea>,而不是可以折疊代碼的風格,向了解的朋友請教.)

Class Con_Convert
 ' ******global message
 private i,j,value0,value1,value2
 
 Private Sub Class_Initialize
   End Sub
   Private Sub Class_Terminate
   End Sub
   
 
 
 
 
 
 ' ==============================================================================
 ' Check Type, Return ture/false
 ' ==============================================================================
    Public Function IsStr(ByVal Value)
        IsStr=true
    End Function
   
    ' ****** check string if is Integer
    Public Function IsInteger(ByVal Value)
        if Trim(Value)="" or IsNull(Value) or IsEmpty(Value) then
            IsInteger=false
        else
            IsInteger = True
            value0=Trim(Value)
            For i = 1 To len(value0)
             If Asc(Mid(value0, i, 1))>= Asc("0") and Asc(Mid(value0, i, 1)) <= Asc("9") Then
             Else
              if Asc(Mid(value0, i, 1))= Asc("-") and i=1 then
                 else
                  IsInteger = false
                  Exit For
                 end if
             End If
         Next
        end if
    End Function
   
    ' ****** check if Value is in range of integer
    ' Only use in this class
    ' Value :
    ' vBound : max
    Private Function IsOverflowInteger(ByVal Value,ByVal vBound)
        if IsInteger(Value) and IsInteger(vBound) then
            IsOverflowInteger=false
            value0=trim(value)
            value1=trim(vBound)
           
            if IsOverflowInteger=false then
                'delete 0 from left
                do while ( left(value0,1)="0" or left(value0,1)="-" )
                    value0=right(value0,len(value0)-1)
                loop
                do while ( left(value1,1)="0" or left(value1,1)="-" )
                    value1=right(value1,len(value1)-1)
                loop
               
                if len(value0)=len(value1) then
                    for i=1 to len(value0)
                        if Asc(mid(value0,i,1)) > Asc(mid(value1,i,1)) or Asc(mid(value0,i,1)) > Asc("9") or Asc(mid(value0,i,1)) < Asc("0") then
                            IsOverflowInteger=true
                            exit for
                        end if
                    next
                else
                    if len(value0)>len(value1) then
                        IsOverflowInteger=true
                    end if
                end if
            end if
        else
            IsOverflowInteger=true
        end if
    End Function
   
   
   
    Public Function IsInt(ByVal Value)
        IsInt=true
        if left(trim(value),1)="-" then
            if IsOverflowInteger(trim(value),"-32768") then
                IsInt=false
            end if
        else
            if IsOverflowInteger(trim(value),"32767") then
                IsInt=false
            end if
        end if
    end function
   
    Public Function IsLng(ByVal Value)
        IsLng=true
        if left(trim(value),1)="-" then
            if IsOverflowInteger(trim(value),"-2147483648") then
                IsLng=false
            end if
        else
            if IsOverflowInteger(trim(value),"2147483647") then
                IsLng=false
            end if
        end if
    End Function
   
   
   
   
    ' **************************************
    ' Decimal
    ' **************************************
    ' ****** check string if is Decimal
    Private Function IsDecimal(ByVal Value)
        dim intDecimalCount
        intDecimalCount=0
        if Trim(Value)="" or IsNull(Value) or IsEmpty(Value) then
            IsDecimal=false
        else
            IsDecimal = True
            value0=Trim(Value)
            For i = 1 To len(value0)
             If Asc(Mid(value0, i, 1))>= Asc("0") and Asc(Mid(value0, i, 1)) <= Asc("9") Then
             Else
                 select case Asc(Mid(value0, i, 1))
                     case Asc("-")
                         if i=1 then
                         else
                             IsDecimal = false
                          Exit For
                         end if
                        
                     case Asc(".")
                         if intDecimalCount<2 then
                             intDecimalCount=intDecimalCount + 1
                         else
                             IsDecimal = false
                          Exit For
                         end if
                        
                     case else
                         IsDecimal = false
                      Exit For
                 end select
             End If
         Next
        end if
    End Function
   
    ' ****** check if Value is in range of Decimal
    ' Only use in this class
    ' Value :
    ' vBound :
    Private Function IsOverflowDecimal(ByVal Value,ByVal vBound)
        if Trim(Value)="" or IsNull(Value) or IsEmpty(Value) or Trim(vBound)="" or IsNull(vBound) or IsEmpty(vBound) then
            IsOverflowDecimal=true
        else
           
        end if
    End Function
   
   
    Public Function IsSng(ByVal Value)
        IsSng=IsDecimal(value)
        ' -340282300000000000000000000000000000000  ~ -0.000000000000000000000000000000000000000000001401298
        ' 0.000000000000000000000000000000000000000000001401298 ~ 340282300000000000000000000000000000000
        ' -3.402823 E38  ~ -1.401298 E-45
        '  1.401298 E-45 ~  3.402823 E38
        
    End Function
   
    Public Function IsDbl(ByVal Value)
        IsDbl=IsDecimal(value)
        ' -1.79769313486232 E308  ~ -4.94065645841247 E-324
        '  4.94065645841247 E-324 ~  1.7976931348623  E308
    End Function
   
    Public Function IsCur(ByVal Value)
        IsCur=IsDecimal(value)
        '-922337203685477.5808 ~ 922337203685477.5807
    End Function
   
   
   
   
   
    Public Function IsBln(ByVal Value)
        if Value=true or Value=false or trim(Value)="1" or trim(Value)="0" then
            IsBln=true
        else
            IsBln=false
        end if
    End Function
   
   
   
    Public Function IsDat(ByVal Value)
        if Trim(Value)="" or IsNull(Value) or IsEmpty(Value) then
            IsDat=false
        else
            IsDat=IsDate(Value)
        end if
    End Function
   
    Public Function IsArr(ByVal Value)
        if Trim(Value)="" or IsNull(Value) or IsEmpty(Value) then
            IsArr=false
        else
            IsArr=IsArray(Value)
        end if
    End Function
   
   
   
   
   
   
   
   
    ' ==============================================================================
 ' Convert Type, Return value/initial value
 ' ==============================================================================
    Public Function ToStr(ByVal Value)
        ToStr=trim(Value)
    End Function
   
    Public Function ToInt(ByVal Value)
        if IsInt(Value) then
            ToInt=Cint(Value)
        else
            ToInt=0
        end if
    End Function
   
    Public Function ToLng(ByVal Value)
        if IsLng(Value) then
            ToLng=clng(Value)
        else
            ToLng=0
        end if
    End Function
   
    Public Function ToSng(ByVal Value)
        if IsSng(Value) then
            ToSng=cSng(Value)
        else
            ToSng=0
        end if
    End Function
   
    Public Function ToDbl(ByVal Value)
        if IsDbl(Value) then
            ToDbl=cDbl(Value)
        else
            ToDbl=0
        end if
    End Function
   
    Public Function ToBln(ByVal Value)
        if IsBln(Value) then
            ToBln=cbool(Value)
        else
            ToBln=false
        end if
    End Function
   
    ' ****** vDecimal : number of decimal places
    Public Function ToCur(ByVal Value)
        if IsCur(Value) then
            ToCur=ccur(Value)
        else
            ToCur=0
        end if
    End Function
   
   
    ' ****** vType : format of date
    Public Function ToDat(ByVal Value)
        if IsDat(Value) then
            ToDat=cdate(value)
        else
            ToDat=""
        end if
    End Function
   
   
   
   
   
    ' ==============================================================================
 ' Format
 ' ==============================================================================
    ' *******************************************************
 'FormatDat
 'vdate
 'vStyle                 0:2008-1-30  1:2008/1/30  2:1/30/2008  3:30/1/2008  4:30-JAN-2008
 '                       10:2008-1    11:2008/1    12:1/2008   
 '                                                 22:JAN-2008
 '                       30:2008-1-30 11:20:20
 '                       40:2008-01-09  
    Public Function FormatDat(ByVal Value, ByVal vStyle)
        dim dateThis,intStyle
  dateThis=ToDat(Value)
     
     intStyle=ToInt(vStyle)
       
        if dateThis="" or isnull(dateThis) then
            FormatDat = ""
        else
      Dim arrMonthArray(12)
         arrMonthArray(1)="JAN"
         arrMonthArray(2)="FEB"
         arrMonthArray(3)="MAR"
         arrMonthArray(4)="APR"
         arrMonthArray(5)="MAY"
         arrMonthArray(6)="JUN"
         arrMonthArray(7)="JUL"
         arrMonthArray(8)="AUG"
         arrMonthArray(9)="SEP"
         arrMonthArray(10)="OCT"
         arrMonthArray(11)="NOV"
         arrMonthArray(12)="DEC"
         
      select case intStyle
          case 1
              FormatDat=cstr(year(dateThis)) &"/"& cstr(month(dateThis)) &"/"& cstr(day(dateThis))
          case 2
              FormatDat=  cstr(month(dateThis)) &"/"& cstr(day(dateThis)) &"/"& cstr(year(dateThis))
          case 3
              FormatDat= cstr(day(dateThis))  &"/"& cstr(month(dateThis)) &"/"& cstr(year(dateThis))
          case 4
              FormatDat= cstr(day(dateThis))  &"-"& arrMonthArray(month(dateThis)) &"-"& cstr(year(dateThis))
         
          case 10
              FormatDat=cstr(year(dateThis)) &"-"& cstr(month(dateThis))
          case 11
              FormatDat=cstr(year(dateThis)) &"/"& cstr(month(dateThis))
          case 12
              FormatDat=  cstr(month(dateThis)) &"/"& cstr(year(dateThis))
         
         
         
          case 22
              FormatDat=  arrMonthArray(month(dateThis)) &"-"& cstr(year(dateThis))
          case 30
              FormatDat=  cstr(year(dateThis)) &"-"& cstr(month(dateThis)) &"-"& cstr(day(dateThis)) &" "& hour(dateThis) &":"& minute(dateThis) &":"& second(dateThis)
         
          case 40
              FormatDat=cstr(year(dateThis)) &"-"& ZeroPad(cstr(month(dateThis)),2) &"-"& ZeroPad(cstr(day(dateThis)),2)
         
         
          case else
              FormatDat=cstr(year(dateThis)) &"-"& cstr(month(dateThis)) &"-"& cstr(day(dateThis))
      end select
  
  end if
    End Function
   
    ' **************
 'FormatCur
 ' **************
 Public Function FormatCur(ByVal Value,ByVal vDecimal)
     FormatCur=Formatcurrency(ToCur(Value),ToInt(vDecimal))
 End Function
 
 Public Function FormatNum(ByVal Value,ByVal vDecimal)
     FormatNum=FormatNumber(ToDbl(Value),ToInt(vDecimal))
 End Function
 
 
 
 
 
 
 
 
 
 ' ==============================================================================
 ' other format
 ' ==============================================================================
 Public Function ToPer(Byval value,Byval value0)
     if Convert.ToDbl(value0)<>0 then
         ToPer = me.FormatNum( Convert.ToDbl(value) / Convert.ToDbl(value0) * 100,2 ) & "% "
     else
         ToPer = "0.00%"
     end if
 End Function
 
 ' ****** value -> Value first code change to uppercase
 Public Function FirstUppercase(ByVal value)
     value0 = trim(value)
     if len(value0)=0 then
         FirstUppercase = ""
     else
         FirstUppercase = UCase(left(value0,1)) & right(value0,len(value0)-1)
     end if
 End Function
 
 
 Public Function SafeSql(ByVal value)
     SafeSql = replace(value,"'","''")
 End Function
End Class

• asp