Fastdb's Chinese Character truncation error

Fastdb's Chinese Character truncation error

In Fastdb C #, if the field type is defined as CLI. FieldType. cli_asciiz, garbled characters may occur when the Chinese character set is inserted,

Tracing code found that during the CopyBufferData process of the string buffer, fastdb directly uses s. length gets the number of characters, rather than the number of bytes. Because the Chinese character occupies two bytes, data copy is incomplete, leading to garbled characters.

The corrected code is as follows:

Protected int bytelengh (string str)
{
// Convert a string to a byte array using Unicode encoding. It stores all strings (including English and Chinese) in 2 bytes.
Byte [] bytestr = System. Text. Encoding. Unicode. GetBytes (str );
Int j = 0;
For (int I = 0; I <bytestr. GetLength (0); I ++)
{
// The remainder 2 is obtained because all the elements in the byte array with double numbers are the first byte of the unicode character.
If (I % 2 = 0)
{
J ++;
}
Else
{
// The singular subscript is the 2nd bytes of the character. If the value of a single character's 2nd bytes is 0, the Unicode character is an English character. Otherwise, the Unicode character is a Chinese character.
If (bytestr [I]> 0)
{
J ++;
}
}
}
Return j;
}
Protected unsafe void setValue (Object Value ){
Switch (CLI. FieldType) (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> type ){
Case CLI. FieldType. cli_oid:
* (Uint *) (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> data. ToPointer () = Convert. ToUInt32 (Value );
Break;
Case CLI. FieldType. cli_int4:
* (Int *) (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> data. ToPointer () = Convert. ToInt32 (Value );
Break;
Case CLI. FieldType. cli_bool:
Case CLI. FieldType. cli_int1:
* (Sbyte *) (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> data. ToPointer () = Convert. ToSByte (Value );
Break;
Case CLI. FieldType. cli_int2:
* (Int16 *) (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> data. ToPointer () = Convert. ToInt16 (Value );
Break;
Case CLI. FieldType. cli_int8:
* (Int64 *) (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> data. ToPointer () = Convert. ToInt64 (Value );
Break;
Case CLI. FieldType. cli_real4:
* (Single *) (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> data. ToPointer () = Convert. ToSingle (Value );
Break;
Case CLI. FieldType. cli_datetime:
Case CLI. FieldType. cli_real8:
* (Double *) (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> data. ToPointer () = Convert. ToDouble (Value );
Break;
Case CLI. FieldType. cli_asciiz:
Case CLI. FieldType. cli_pasciiz:
String s = Value. ToString ();
IntPtr str = Marshal. StringToHGlobalAnsi (s );
// Correct the Chinese character truncation error
Try {
CopyBufferData (CLI. FieldType) (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> type, bytelengh (s), str );
}
Finally {
Marshal. FreeCoTaskMem (str );
}
Break;
Case CLI. FieldType. cli_array_of_int1:
If (Value is byte []) {
Byte [] arr = (byte []) Value;
Int len = arr. Length;
SetBufferTypeAndSize (CLI. UnmanagedBuffer *) buffer. ToPointer (), CLI. FieldType. cli_array_of_int1, len, false );
Byte * dst = (byte *) (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> data. ToPointer ();
For (int I = 0; I <len; I ++ ){
* Dst ++ = arr [I];
}
Break;
} Else {
Throw new CliError ("getValue: Unsupported conversion type! "+ Enum. GetName (typeof (CLI. FieldType), (CLI. UnmanagedBuffer *) buffer. ToPointer ()-> type ));
}
Default:
Throw new CliError ("Unsupported type:" + Enum. getName (typeof (CLI. fieldType), (CLI. fieldType) (CLI. unmanagedBuffer *) buffer. toPointer ()-> type ));
}
}

You can also use System. Text. Encoding. Default. GetBytes (s). Length. However, if the Length of the wonderful System may change, it has not been tested. If you are interested, try it.

I hope it will be helpful for my friends who use c # To develop fastdb.

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