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C# TdsParserStateObject.TryReadPlpBytes方法代码示例

本文整理汇总了C#中System.Data.SqlClient.TdsParserStateObject.TryReadPlpBytes方法的典型用法代码示例。如果您正苦于以下问题:C# TdsParserStateObject.TryReadPlpBytes方法的具体用法?C# TdsParserStateObject.TryReadPlpBytes怎么用?C# TdsParserStateObject.TryReadPlpBytes使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在System.Data.SqlClient.TdsParserStateObject的用法示例。


在下文中一共展示了TdsParserStateObject.TryReadPlpBytes方法的3个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C#代码示例。

示例1: TryCreate

        // Reads off from the network buffer and caches bytes. Only reads one column value in the current row.
        static internal bool TryCreate(SqlMetaDataPriv metadata, TdsParser parser, TdsParserStateObject stateObj, out SqlCachedBuffer buffer)
        {
            int cb = 0;
            ulong plplength;
            byte[] byteArr;

            List<byte[]> cachedBytes = new List<byte[]>();
            buffer = null;

            // the very first length is already read.
            if (!parser.TryPlpBytesLeft(stateObj, out plplength))
            {
                return false;
            }
            // For now we  only handle Plp data from the parser directly.
            Debug.Assert(metadata.metaType.IsPlp, "SqlCachedBuffer call on a non-plp data");
            do
            {
                if (plplength == 0)
                    break;
                do
                {
                    cb = (plplength > (ulong)_maxChunkSize) ? _maxChunkSize : (int)plplength;
                    byteArr = new byte[cb];
                    if (!stateObj.TryReadPlpBytes(ref byteArr, 0, cb, out cb))
                    {
                        return false;
                    }
                    Debug.Assert(cb == byteArr.Length);
                    if (cachedBytes.Count == 0)
                    {
                        // Add the Byte order mark if needed if we read the first array
                        AddByteOrderMark(byteArr, cachedBytes);
                    }
                    cachedBytes.Add(byteArr);
                    plplength -= (ulong)cb;
                } while (plplength > 0);
                if (!parser.TryPlpBytesLeft(stateObj, out plplength))
                {
                    return false;
                }
            } while (plplength > 0);
            Debug.Assert(stateObj._longlen == 0 && stateObj._longlenleft == 0);

            buffer = new SqlCachedBuffer(cachedBytes);
            return true;
        }
开发者ID:ChuangYang,项目名称:corefx,代码行数:48,代码来源:SqlCachedBuffer.cs

示例2: TryReadSqlValue

        internal bool TryReadSqlValue(SqlBuffer value, SqlMetaDataPriv md, int length, TdsParserStateObject stateObj)
        {
            bool isPlp = md.metaType.IsPlp;
            byte tdsType = md.tdsType;

            Debug.Assert(isPlp || !IsNull(md.metaType, (ulong)length), "null value should not get here!");
            if (isPlp)
            {
                // We must read the column value completely, no matter what length is passed in
                length = Int32.MaxValue;
            }
            switch (tdsType)
            {
                case TdsEnums.SQLDECIMALN:
                case TdsEnums.SQLNUMERICN:
                    if (!TryReadSqlDecimal(value, length, md.precision, md.scale, stateObj))
                    {
                        return false;
                    }
                    break;

                case TdsEnums.SQLUDT:
                    throw SQL.UnsupportedFeatureAndToken(_connHandler, SqlDbType.Udt.ToString());
                case TdsEnums.SQLBINARY:
                case TdsEnums.SQLBIGBINARY:
                case TdsEnums.SQLBIGVARBINARY:
                case TdsEnums.SQLVARBINARY:
                case TdsEnums.SQLIMAGE:
                    byte[] b = null;

                    // If varbinary(max), we only read the first chunk here, expecting the caller to read the rest
                    if (isPlp)
                    {
                        // If we are given -1 for length, then we read the entire value,
                        // otherwise only the requested amount, usually first chunk.
                        int ignored;
                        if (!stateObj.TryReadPlpBytes(ref b, 0, length, out ignored))
                        {
                            return false;
                        }
                    }
                    else
                    {
                        //Debug.Assert(length > 0 && length < (long)(Int32.MaxValue), "Bad length for column");
                        b = new byte[length];
                        if (!stateObj.TryReadByteArray(b, 0, length))
                        {
                            return false;
                        }
                    }

                    value.SqlBinary = new SqlBinary(b, true);   // doesn't copy the byte array

                    break;

                case TdsEnums.SQLCHAR:
                case TdsEnums.SQLBIGCHAR:
                case TdsEnums.SQLVARCHAR:
                case TdsEnums.SQLBIGVARCHAR:
                case TdsEnums.SQLTEXT:
                case TdsEnums.SQLNCHAR:
                case TdsEnums.SQLNVARCHAR:
                case TdsEnums.SQLNTEXT:
                    if (!TryReadSqlStringValue(value, tdsType, length, md.encoding, isPlp, stateObj))
                    {
                        return false;
                    }
                    break;

                case TdsEnums.SQLXMLTYPE:
                    // We store SqlCachedBuffer here, so that we can return either SqlBinary, SqlString or SqlXmlReader.
                    SqlCachedBuffer sqlBuf;
                    if (!SqlCachedBuffer.TryCreate(md, this, stateObj, out sqlBuf))
                    {
                        return false;
                    }

                    value.SqlCachedBuffer = sqlBuf;
                    break;

                case TdsEnums.SQLDATE:
                case TdsEnums.SQLTIME:
                case TdsEnums.SQLDATETIME2:
                case TdsEnums.SQLDATETIMEOFFSET:
                    if (!TryReadSqlDateTime(value, tdsType, length, md.scale, stateObj))
                    {
                        return false;
                    }
                    break;

                default:
                    Debug.Assert(!isPlp, "ReadSqlValue calling ReadSqlValueInternal with plp data");
                    if (!TryReadSqlValueInternal(value, tdsType, length, stateObj))
                    {
                        return false;
                    }
                    break;
            }

            Debug.Assert((stateObj._longlen == 0) && (stateObj._longlenleft == 0), "ReadSqlValue did not read plp field completely, longlen =" + stateObj._longlen.ToString((IFormatProvider)null) + ",longlenleft=" + stateObj._longlenleft.ToString((IFormatProvider)null));
//.........这里部分代码省略.........
开发者ID:nnyamhon,项目名称:corefx,代码行数:101,代码来源:TdsParser.cs

示例3: TryReadSqlValue

        internal bool TryReadSqlValue(SqlBuffer value,
                                      SqlMetaDataPriv md,
                                      int length,
                                      TdsParserStateObject stateObj,
                                      SqlCommandColumnEncryptionSetting columnEncryptionOverride, 
                                      string columnName) {
            bool isPlp = md.metaType.IsPlp;
            byte tdsType = md.tdsType;

            Debug.Assert(isPlp || !IsNull(md.metaType, (ulong)length), "null value should not get here!");
            if (isPlp) {
                // We must read the column value completely, no matter what length is passed in
                length = Int32.MaxValue;
            }

            //DEVNOTE: When modifying the following routines (for deserialization) please pay attention to 
            // deserialization code in DecryptWithKey () method and modify it accordingly.
            switch (tdsType) {
                case TdsEnums.SQLDECIMALN:
                case TdsEnums.SQLNUMERICN:
                    if (!TryReadSqlDecimal(value, length, md.precision, md.scale, stateObj)) {
                        return false;
                    }
                    break;

                case TdsEnums.SQLUDT:
                case TdsEnums.SQLBINARY:
                case TdsEnums.SQLBIGBINARY:
                case TdsEnums.SQLBIGVARBINARY:
                case TdsEnums.SQLVARBINARY:
                case TdsEnums.SQLIMAGE:
                    byte[] b = null;

                    // If varbinary(max), we only read the first chunk here, expecting the caller to read the rest
                    if (isPlp) {
                        // If we are given -1 for length, then we read the entire value,
                        // otherwise only the requested amount, usually first chunk.
                        int ignored;
                        if (!stateObj.TryReadPlpBytes(ref b, 0, length, out ignored)) {
                            return false;
                        }
                    }
                    else {
                        //Debug.Assert(length > 0 && length < (long)(Int32.MaxValue), "Bad length for column");
                        b = new byte[length];
                        if (!stateObj.TryReadByteArray(b, 0, length)) {
                            return false;
                        }
                    }

                    if (md.isEncrypted 
                        && ((columnEncryptionOverride == SqlCommandColumnEncryptionSetting.Enabled
                            || columnEncryptionOverride == SqlCommandColumnEncryptionSetting.ResultSetOnly)
                            || (columnEncryptionOverride == SqlCommandColumnEncryptionSetting.UseConnectionSetting
                                && _connHandler != null && _connHandler.ConnectionOptions != null
                                && _connHandler.ConnectionOptions.ColumnEncryptionSetting == SqlConnectionColumnEncryptionSetting.Enabled))) {
                        try {
                            // CipherInfo is present, decrypt and read
                            byte[] unencryptedBytes = SqlSecurityUtility.DecryptWithKey(b, md.cipherMD, _connHandler.ConnectionOptions.DataSource);

                            if (unencryptedBytes != null) {
                                DeserializeUnencryptedValue(value, unencryptedBytes, md, stateObj, md.NormalizationRuleVersion);
                            }
                        }
                        catch (Exception e) {
                            throw SQL.ColumnDecryptionFailed(columnName, null, e);
                        }
                    }
                    else {
                        value.SqlBinary = new SqlBinary(b, true);   // doesn't copy the byte array
                    }
                    break;

                case TdsEnums.SQLCHAR:
                case TdsEnums.SQLBIGCHAR:
                case TdsEnums.SQLVARCHAR:
                case TdsEnums.SQLBIGVARCHAR:
                case TdsEnums.SQLTEXT:
                case TdsEnums.SQLNCHAR:
                case TdsEnums.SQLNVARCHAR:
                case TdsEnums.SQLNTEXT:
                    if (!TryReadSqlStringValue(value, tdsType, length, md.encoding, isPlp, stateObj)) {
                        return false;
                    }
                    break;

                case TdsEnums.SQLXMLTYPE:
                    // We store SqlCachedBuffer here, so that we can return either SqlBinary, SqlString or SqlXmlReader.
                    SqlCachedBuffer sqlBuf;
                    if (!SqlCachedBuffer.TryCreate(md, this, stateObj, out sqlBuf)) {
                        return false;
                    }

                    value.SqlCachedBuffer = sqlBuf;
                    break;

                case TdsEnums.SQLDATE:
                case TdsEnums.SQLTIME: 
                case TdsEnums.SQLDATETIME2:
                case TdsEnums.SQLDATETIMEOFFSET:
//.........这里部分代码省略.........
开发者ID:iskiselev,项目名称:JSIL.NetFramework,代码行数:101,代码来源:TdsParser.cs


注:本文中的System.Data.SqlClient.TdsParserStateObject.TryReadPlpBytes方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。