在运行时扩展报表系统之报表指令

with This
    .oDirectiveHandlers = createobject('Collection')
    loHandler = newobject('SFDynamicForeColorDirective', ;
        'SFReportListener.vcx')
    .oDirectiveHandlers.Add(loHandler, ccDIRECTIVE_FORECOLOR)
    loHandler = newobject('SFDynamicBackColorDirective', ;
        'SFReportListener.vcx')
    .oDirectiveHandlers.Add(loHandler, ccDIRECTIVE_BACKCOLOR)
    loHandler = newobject('SFDynamicStyleDirective', ;
        'SFReportListener.vcx')
    .oDirectiveHandlers.Add(loHandler, ccDIRECTIVE_STYLE)
    loHandler = newobject('SFDynamicAlphaDirective', ;
        'SFReportListener.vcx')
    .oDirectiveHandlers.Add(loHandler, ccDIRECTIVE_ALPHA)
endwith

local laLines[1], ;
    lnLines, ;
    lnI, ;
    lcLine, ;
    lnPos, ;
    lcClause, ;
    lcExpr
    loHandler, ;
    loDirective
with This
* 处理在USER备注中的任何代码行

    lnLines = alines(laLines, USER)
    for lnI = 1 to lnLines
        lcLine = alltrim(laLines[lnI])

* 如果我们找到了一个listener 指令，并且它是我们支持的指令，
* 就把该指令和它的表达式添加到我们的集合中去
* (这个集合在第一次被用到的时候建立).

        if upper(left(lcLine, 10)) = ccDIRECTIVE_LISTENER
            lcLine   = substr(lcLine, 12)
            lnPos    = at('=', lcLine)
            lcClause = alltrim(left(lcLine, lnPos - 1))
            lcExpr   = alltrim(substr(lcLine, lnPos + 1))
            try
                loHandler   = .oDirectiveHandlers.Item(upper(lcClause))
                lcExpr      = loHandler.ProcessExpression(lcExpr)
                loDirective = createobject('Empty')
                addproperty(loDirective, 'DirectiveHandler', lcClause)
                addproperty(loDirective, 'Expression',       lcExpr)

* 建立一个当前记录中所有指令的集合

                if vartype(.aRecords[recno()]) <> 'O'
                    .aRecords[recno()] = createobject('Collection')
                endif vartype(.aRecords[recno()]) <> 'O'
                .aRecords[recno()].Add(loDirective)
            catch
            endtry
        endif upper(left(lcLine, 10)) = ccDIRECTIVE_LISTENER
    next lnI
endwith

lparameters tnFRXRecno,  toObjProperties
local loDirective,  loHandler

with This
    if vartype(.aRecords[tnFRXRecno]) = 'O'
        for each loDirective in .aRecords[tnFRXRecno]
            loHandler = ;
                .oDirectiveHandlers.Item(loDirective.DirectiveHandler)
            loHandler.HandleDirective(This, loDirective.Expression, ;
                toObjProperties)
        next loDirective
    endif vartype(.aRecords[tnFRXRecno]) = 'O'
endwith
dodefault(tnFRXRecno, toObjProperties)

lparameters tcExpression
local lcExpression
lcExpression = strtran(tcExpression, '#NORMAL#',;
    transform(FRX_FONTSTYLE_NORMAL))
lcExpression = strtran(lcExpression, '#BOLD#', ;
    transform(FRX_FONTSTYLE_BOLD))
lcExpression = strtran(lcExpression, '#ITALIC#',;
    transform(FRX_FONTSTYLE_ITALIC))
lcExpression = strtran(lcExpression, '#UNDERLINE#', ;
    transform(FRX_FONTSTYLE_UNDERLINED))
lcExpression = strtran(lcExpression, '#STRIKETHRU#', ;
    transform(FRX_FONTSTYLE_STRIKETHROUGH))
return lcExpression

lparameters toListener,  tcExpression,  toObjProperties
local lnStyle

lnStyle = evaluate(tcExpression)
if vartype(lnStyle) = 'N'
    toObjProperties.FontStyle = lnStyle
    toObjProperties.Reload    = .T.
endif vartype(lnStyle) = 'N'
SFDynamicAlphaDirective非常类似于SFDynamicStyleDirective，但它是把报表对象的PenAlpha属性设置为指定的值。给它指定指令要使用下面这样的语法：
*:LISTENER ALPHA = AlphaExpression
SFDynamicColorDirective非常类似于SFDynamicStyleDirective，但它处理的是报表对象的颜色而不是字体样式。跟样式一样，颜色必须以RGB值的形式来指定，因此SFDynamicColorDirective支持以文本来指定颜色，例如#RED#、#BLUE#、以及#YELLOW#，使用下面的语法来指定指令：
*:LISTENER FORECOLOR = ColorExpression
*:LISTENER BACKCOLOR = ColorExpression
这里的ColorExpression是一个可以被运算为期望的颜色的表达式。
在HandleDirective方法中的代码类似于SFDynamicStyleDirective，但它调用SetColor而不是设置FontStyle属性。SetColor抽象在这个类中，而它具体实现是在SFDynamicColorDirective的两个子类中：SFDynamicBackColorDirective和SFDynamicForeColorDirective。这里是来自SFDynamicBackColorDirective的代码，用来演示颜色是如何被设置的：
lparameters toObjProperties,  tnColor

with toObjProperties
    .FillRed   = bitand(tnColor, 0x0000FF)
    .FillGreen = bitrshift(bitand(tnColor, 0x00FF00), 8)
    .FillBlue  = bitrshift(bitand(tnColor, 0xFF0000), 16)
Endwith

use _samples + 'Northwind\orders'
loListener = newobject('SFReportListenerDirective', 'SFReportListener.vcx')
report form TestDynamicFormatting.FRX preview object loListener next 20

lparameters toListener,  tcExpression,  toObjProperties
local lcText,  lcNewText,  lnI,  lcWord

store toObjProperties.Text to lcText, lcNewText
for lnI = 1 to getwordcount(lcText)
    lcWord = getwordnum(lcText, lnI)
    if seek(upper(lcWord), 'STRINGS', 'ENGLISH')
        lcNewText = strtran(lcNewText, lcWord, trim(evaluate('STRINGS.' +;
        gcLanguage)))
    endif seek(upper(lcWord) ...
next lnI

if not lcNewText == toObjProperties.Text
    toObjProperties.Text   = lcNewText
    toObjProperties.Reload = .T.
endif not lcNewText == toObjProperties.Text

use _samples + 'Northwind\customers'
loListener=newobject('SFReportListenerDirective', 'SFReportListener.vcx')
loHandler  = newobject('SFTranslateDirective', 'SFReportListener.vcx')
loListener.oDirectiveHandlers.Add(loHandler, 'TRANSLATE')
gcLanguage = 'PigLatin'
report form TestTranslate.FRX preview object loListener

lparameters tnFRXRecno, ;
    tnLeft, ;
    tnTop, ;
    tnWidth, ;
    tnHeight, ;
    tnObjectContinuationType, ;
    tcContentsToBeRendered, ;
    tnGDIPlusImage
local lnAngle, lnState

with This
* 如果应该要旋转这个对象，就这么做
    lnAngle = evaluate(evl(.aRecords[tnFRXRecno], '0'))
    if lnAngle <> 0
        * 保存图形句柄的当前状态
        .oGDIGraphics.Save(@lnState)
        .nState = lnState

        * 将坐标原点0,0 移动到我们希望它处于的位置，
        * 这样，当我们开始旋转的时候，是在围绕着恰当的点旋转
        .oGDIGraphics.TranslateTransform(tnLeft, tnTop)

        * Change the angle at which the draw will occur.
        .oGDIGraphics.RotateTransform(lnAngle)

        * 恢复坐标原点 0,0
        .oGDIGraphics.TranslateTransform(-tnLeft, -tnTop)
    endif lnAngle <> 0

    * 执行正常的行为
    dodefault(tnFRXRecno, tnLeft, tnTop, tnWidth, tnHeight, ;
        tnObjectContinuationType, tcContentsToBeRendered, tnGDIPlusImage)
endwith

with This
    if .nState <> 0
        .oGDIGraphics.Restore(.nState)
        .nState = 0
    endif .nState <> 0

    *执行正常的行为
    dodefault()
endwith

use _samples + 'Northwind\orders'
loListener = newobject('SFRotateDirective', 'SFReportListener.vcx')
report form TestRotate.FRX preview object loListener next 20