Le portail francophone de la géomatique

' Table.Modify
' Renames or modifies fields in a Table document

' Assumes that the base table is a shapefile or dBase (.DBF) file
' Saves the old table with a .BAK extension
' At this point, only DECIMAL and CHAR fields are supported

'**** see if directory and dBase file write-protected

theTable = av.GetActiveDoc
tabName = theTable.GetName
tabExt = theTable.GetWin.ReturnExtent
tabOrigin = theTable.GetWin.ReturnOrigin
theVTab = theTable.GetVTab
theFName = theVTab.GetBaseTableFileName
theDir = theFName.ReturnDir
theTitle = "Modify"
if (File.IsWritable(theDir).Not) then
   MsgBox.Error("Cannot write to directory.",theTitle)
   return nil
end
if (File.IsWritable(theFName).Not) then
   MsgBox.Error("File is not writable.",theTitle)
   return nil
end

'**** get list of field names

fl = List.Make
for each f in theVTab.GetFields
   fnm = f.GetName
   ft = f.GetType.AsString.AsTokens("_").Get(1)
   if ((ft = "CHAR") or (ft = "DECIMAL")) then
      fl.Add(fnm.AsString)
   end
end

'**** get modifications

f_list = List.Make
modlist = List.Make
modfield = true
theMsg = "Enter modifications"
theLabels = {"Name","Type","Width","Precision"}
while (modfield)
   f = MsgBox.ChoiceAsString(fl,"Select field to modify",theTitle)
   if (f = nil) then
      return nil
   elseif (f_list.FindByValue(f) > -1) then
      MsgBox.Info("Field already selected",theTitle)
   else
      theField = theVTab.FindField(f)
      theType = theField.GetType.AsString.AsTokens("_").Get(1)
      theWidth = theField.GetWidth.AsString
      thePrecision = theField.GetPrecision.AsString
      theDefaults = {f,theType,theWidth,thePrecision}
      result = MsgBox.MultiInput(theMsg,theTitle,theLabels,theDefaults)
      if (result = nil) then
         return nil
      end
      newName = result.Get(0)
      nt = result.Get(1)
      if ((nt = "CHAR") or (nt = "DECIMAL")) then
         newType = ("#FIELD_"+nt).AsEnum
      else
         MsgBox.Error("Unsupported type",theTitle)
         return nil
      end
      newWidth = result.Get(2).AsNumber
      newPrecision = result.Get(3).AsNumber
      f_list.Add(f)
      modlist.Add({newName,newType,newWidth,newPrecision})
   end
   modfield = MsgBox.MiniYesNo("Modify another field?",false)
end

'**** generate field list

oldFields = List.Make
newFields = List.Make
for each f in theVTab.GetFields
   fnm = f.GetName
   if (fnm <> "Shape") then
      i = f_list.FindByValue(fnm)
      if (i > -1) then
         nm = modlist.Get(i).Get(0)
         nt = modlist.Get(i).Get(1)
         nw = modlist.Get(i).Get(2)
         np = modlist.Get(i).Get(3)
         nf = Field.Make(nm,nt,nw,np)
         newFields.Add(nf)
      else
         newFields.Add(f.Clone)
      end
      oldFields.Add(f)
   end
end

'**** generate scratch file

tmpFName = theDir.MakeTmp("tmp","dbf")
tmpVTab = VTab.MakeNew(tmpFName,dBase)
tmpVTab.AddFields(newFields)

'**** populate records

i_last = newFields.Count - 1
numdone = 0
numrec = theVTab.GetNumRecords
for each r in theVTab
   r2 = tmpVTab.AddRecord
   for each i in 0..i_last
      of = oldFields.Get(i)
      nf = newFields.Get(i)
      v = theVTab.ReturnValue(of,r)
      if (nf.IsTypeString) then
         if (v.Is(Number)) then
            theVal = v.AsString
         else
            theVal = v
         end
      else
         if (v.Is(String)) then
            theVal = v.AsNumber
         else
            theVal = v
         end
      end
      tmpVTab.SetValue(nf,r2,theVal)
   end
   numdone = numdone + 1
   av.SetStatus(numdone / numrec * 100)
end
tmpVTab.Flush
tmpVTab.DeActivate
tmpVTab = nil
theVTab.DeActivate
theVTab = nil
av.GetProject.RemoveDoc(theTable)
theTable = nil
av.PurgeObjects
av.ClearStatus

'**** rename files

bakFName = FileName.Make(theFName.AsString)
bakFName.SetExtension("bak")
File.Copy(theFName,bakFName)
File.Copy(tmpFName,theFName)
File.Delete(tmpFName)

'**** create new table doc

theVTab = VTab.Make(theFName,false,false)
theTable = Table.Make(theVTab)
av.GetProject.AddDoc(theTable)
theTable.SetName(tabName)
theTable.GetWin.MoveTo(tabOrigin.GetX,tabOrigin.GetY)
theTable.GetWin.Resize(tabExt.GetX,tabExt.GetY)
theTable.GetWin.Activate

return nil