当我尝试提取其中存储了表情符号的 nvarchar 列值时，VB.net 中的数据显示为“??”

Question

当我尝试使用 VB.net 从数据库中提取表情符号值时，表情符号显示为“??”

我需要在我的存储过程中进行某种类型的转换吗？

Answer 1

Private Function DisplayEmoji(input As String) As String
    Dim output As New StringBuilder()
    Dim enumerator = StringInfo.GetTextElementEnumerator(input)
    While enumerator.MoveNext()
        Dim chunk As String = enumerator.GetTextElement()
        If Char.IsSurrogatePair(chunk, 0) Then
            output.Append("<img src=""" + "https://abs.twimg.com/emoji/v1/72x72/" + Char.ConvertToUtf32(chunk, 0).ToString("x") + ".png"" style=""height:1.5em; width:1.5em;"">")
        Else
            output.Append(chunk)
        End If
    End While
    Return output.ToString()
End Function

或者插入您的图像 Blob 类型并读取 sql。

Dim filePath As String = Server.MapPath("APP_DATA/test.png")
Dim filename As String = Path.GetFileName(filePath)

Dim fs As FileStream = New FileStream(filePath, FileMode.Open, FileAccess.Read)
Dim br As BinaryReader = New BinaryReader(fs)
Dim bytes As Byte() = br.ReadBytes(Convert.ToInt32(fs.Length))
br.Close()
fs.Close()

将图像插入数据库

Dim strQuery As String = "insert into tblFiles(Name, ContentType, Data) values (@Name, @ContentType, @Data)"
Dim cmd As SqlCommand = New SqlCommand(strQuery)
cmd.Parameters.Add("@Name", SqlDbType.VarChar).Value = filename
cmd.Parameters.Add("@ContentType", SqlDbType.VarChar).Value = "image/png"
cmd.Parameters.Add("@Data", SqlDbType.Binary).Value = bytes
InsertUpdateData(cmd)

插入更新数据

Public Function InsertUpdateData(ByVal cmd As SqlCommand) As Boolean
    Dim strConnString As String = System.Configuration.
    ConfigurationManager.ConnectionStrings("conString").ConnectionString
    Dim con As New SqlConnection(strConnString)
    cmd.CommandType = CommandType.Text
    cmd.Connection = con
    Try
      con.Open()
      cmd.ExecuteNonQuery()
      Return True
    Catch ex As Exception
      Response.Write(ex.Message)
      Return False
    Finally
      con.Close()
      con.Dispose()
    End Try
End Function

当我尝试提取其中存储了表情符号的 nvarchar 列值时，VB.net 中的数据显示为“??”

When I try to pull nvarchar column value that has an emojis stored in it, the data in VB.net it displays as '??'

vb.net

nvarchar

utf-8

sql-server-2008