插入图片,分两步,首先必须插入当前记录但不包括图片,然后定位到数据库中该条记录,更新图片字段,如下所示:
oracleCommand.CommandText = "SELECT image FROM table WHERE (id = :id) FOR UPDATE";
oracleCommand.Parameters.Add(new System.Data.OracleClient.OracleParameter("id", OracleType.VarChar, 16, "id"));
oracleCommand.Parameters["id"].Value = id;//your record id
OracleDataReader dataReader = oracleCommand.ExecuteReader();
while(dataReader.Read())
{
if (dataReader["image"] != DBNull.Value)
{
OracleLob mBlob = dataReader.GetOracleLob(dataReader.GetOrdinal("image"));
FileStream FStream = new FileStream
(survey_image,FileMode.Open,FileAccess.Read);
//图片最大为10k
byte[] bArr = new byte[10000];
int bArrLen = 0;
bArrLen = FStream.Read(bArr,0,10000);
mBlob.Write(bArr,0,bArrLen);
mBlob.Position = 0;
}
}
dataReader.Close();读取参照一下就可以了
oracleCommand.CommandText = "SELECT image FROM table WHERE (id = :id) FOR UPDATE";
oracleCommand.Parameters.Add(new System.Data.OracleClient.OracleParameter("id", OracleType.VarChar, 16, "id"));
oracleCommand.Parameters["id"].Value = id;//your record id
OracleDataReader dataReader = oracleCommand.ExecuteReader();
while(dataReader.Read())
{
if (dataReader["image"] != DBNull.Value)
{
OracleLob mBlob = dataReader.GetOracleLob(dataReader.GetOrdinal("image"));
FileStream FStream = new FileStream
(survey_image,FileMode.Open,FileAccess.Read);
//图片最大为10k
byte[] bArr = new byte[10000];
int bArrLen = 0;
bArrLen = FStream.Read(bArr,0,10000);
mBlob.Write(bArr,0,bArrLen);
mBlob.Position = 0;
}
}
dataReader.Close();读取参照一下就可以了
这是我的原代码:
OleDbConnection mycon=new OleDbConnection(Base.Base.getConnectionString());
mycon.Open();
da.SelectCommand= new System.Data.OleDb.OleDbCommand("select ZDH,TH from lstowngkcx.T1 where ZDH='"+txt1.Text.Trim()+"'",mycon);
da.Fill(ds,"lstowngkcx.T1");
dv1=new System.Data.DataView(ds.Tables["lstowngkcx.T1"]);
if (dv1.Count > 0)
{
this.DR1 =this.dv1[0].Row;
if(!Information.IsDBNull(RuntimeHelpers.GetObjectValue(this.DR1["TH"]))) {
this.Response.BinaryWrite(((byte[]) this.DR1["TH"])); }
else
{
Response.Write("暂无照片");
}
}
else
{
Response.Write("暂无照片");
}
mycon.Close();
大家帮我看看哪错了.
报错提示为:
未指定的错误发生了一个 Oracle 错误,但无法从 Oracle 中检索错误信息。数据类型不被支持。
说明: 执行当前 Web 请求期间,出现未处理的异常。请检查堆栈跟踪信息,以了解有关该错误以及代码中导致错误的出处的详细信息。 异常详细信息: System.Data.OleDb.OleDbException: 未指定的错误发生了一个 Oracle 错误,但无法从 Oracle 中检索错误信息。数据类型不被支持。源错误: 行 73: da.Fill(ds,"lstowngkcx.T1");