C#读取与保存Oracle BLOB数据操作教程

using System;
using System.Data.OracleClient;
using System.Data;
using System.IO;
using System.Windows.Forms;


namespace OraclePDF
{
    public class OracleBlobControl
    {
        private string constr = "data source=xxxx;password=xxxx;persist security info=True;user id=xxxx";
        private string tempFilePath = @"\";
        OracleConnection Conn = null;
        OracleCommand cmd = null;
        /// <summary>
        /// 数据库连接串
        /// </summary>
        public string Constr
        {
            get { return constr; }
            set { constr = value; }
        }
        /// <summary>
        /// 临时文件目录
        /// </summary>
        public string TempFilePath
        {
            get { return tempFilePath; }
            set { tempFilePath = value;}

        }


        /// <summary>
        /// 将文件用blob格式保存在数据库中 blobName：sql语句中的blobs列名
        /// </summary>
        /// <param name="FilePath"></param>
        /// <param name="sql"></param>
        /// <param name="blobName"></param>
        /// <returns></returns>
        public string SaveBlob(string FilePath,string sql,string  blobName)
        {
           // string sql = "insert into CHY_BLOB_TEST(id,big) values('" + System.DateTime.Now.ToShortTimeString() + "',:a)";
            try
            {
                //文件流
                Byte[] blob = GetblobByFilePath(FilePath);
                //初始化数据库连接
                init(sql);
                //绑定数据
                OracleParameter param = new OracleParameter(blobName, OracleType.Blob, blob.Length, ParameterDirection.Input, false, 0, 0, null, DataRowVersion.Current, blob);
                cmd.Parameters.Add(param);
                //执行
                cmd.ExecuteNonQuery();

                return "1";

            }
            catch (Exception ex)
            {