Powerbuilder：在没有 bom 的情况下将 UTF-8 转换为 UTF-8答案

【问题标题】：Powerbuilder: Converting UTF-8 to UTF-8 without bomPowerbuilder：在没有 bom 的情况下将 UTF-8 转换为 UTF-8
【发布时间】：2020-07-29 04:02:07
【问题描述】：

晚安，我需要将文本文件从 UTF-8 转换为 UTF-8，而无需在 powerbuilder 中使用 bom 我可以识别并应该从文本中删除 bom，但是当我重新录制它时会继续使用 bom，请帮助

                integer li_fnum
                long ll_bytes
                
                li_fnum = FileOpen(ls_archivo, StreamMode!)
                ll_bytes = FileReadEx(li_fnum, lblb_file_contents)

                if len(lblb_file_contents) >= 3 then
                        GetByte(lblb_file_contents, 1, lbt_1)
                        GetByte(lblb_file_contents, 2, lbt_2)
                        GetByte(lblb_file_contents, 3, lbt_3)
                    if lbt_1 = 239 and lbt_2 = 187 and lbt_3 = 191 then // BOM for UTF8 = EF    BB BF
                        // BOM is found - remove it from the blob
                        lblb_file_contents = BlobMid(lblb_file_contents, 4, len(lblb_file_contents) - 3)
                        // Check the truncated contents once again
                        if len(lblb_file_contents) = 0 then
                        MessageBox("Error", "There's no data in the file!", StopSign!)
                        return
                        end if
                    end if
                end if

【问题讨论】：

您可以删除长度参数，没有它，它将返回偏移量为 4 的 blob，例如BlobMid(lbl_file_contents, 4) 顺便说一句，这可能会有所帮助> stackoverflow.com/questions/22336948/…
经过多次尝试，还是去掉了编码，还是非常感谢

标签： utf-8 powerbuilder

【解决方案1】：

您将数据类型 text 转换为 blob 并使用编码 UTF-8 并写下文件：

i=FileWriteEx(f, blob(text,EncodingUTF8!) )

【讨论】：

【解决方案2】：

Create function remove_utf8_bom (String as_file)

 Integer    li_fnum    
 Long       ll_bytes    
 String     ls_file_contents    
 Blob       lblb_file_contents     
 Byte       lbt_1, lbt_2, lbt_3
 
 li_fnum = FileOpen(as_file, StreamMode!)

 ll_bytes = FileReadEx(li_fnum, lblb_file_contents)

 FileClose(li_fnum)

 if len(lblb_file_contents) >= 3 then

            GetByte(lblb_file_contents, 1, lbt_1)    
            GetByte(lblb_file_contents, 2, lbt_2)    
            GetByte(lblb_file_contents, 3, lbt_3)

      if lbt_1 = 239 and lbt_2 = 187 and lbt_3 = 191 then // BOM for UTF8 = EF    BB BF
            // BOM is found - remove it from the blob
            lblb_file_contents = BlobMid(lblb_file_contents, 4, len(lblb_file_contents) - 3)

            // Check the truncated contents once again
            if len(lblb_file_contents) = 0 then    
                //MessageBox("Error", "There's no data in the file!", StopSign!)
                return    
            end if

      end if

 end if
 
 li_fnum = FileOpen(as_file, StreamMode!, Write!, Shared!, Replace!)    
 FileWriteEx(li_fnum, blob(string(lblb_file_contents, EncodingUTF8!),EncodingUTF8!) )    
 FileClose(li_fnum)

【讨论】：

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