On Tuesday, 4 December 2012 at 07:59:40 UTC, Sam Hu wrote:
Greetings!
Any help would be much appreicated in advance as I've really
struggled for quite long time!
I wrote a class wrapper for MS ODBC Access database.When I try
to run query on an Access database file,all fields contains
English character are fine with the result,but for those Asian
characters like Chinese,the result shows blank in DFL gui form
and shows mess (unrecognizable under console).I think maybe the
problem is in the fetchAll function which I provided as below
together with the other main parts of the class:
Client code (DFL form):
[code]
protected void onReadClick(Object sender,EventArgs e)
{
Odbc odbc=new Odbc;
odbc.connect("artistdb","","");
if(!odbc.isOpen)
{
throw new Exception("Failed to connect to ODBC");
return;
}
auto record=odbc.fetchAll("select * from artists where
artistid="~txtSearch.text~";");
txtID.text=to!string(record[0][0]);
txtName.text=to!string(record[0][1]);
odbc.close;
}
[/code]
ODBC wrapper class:
[code]
SQLRETURN SQLExecDirectUTF8(SQLHSTMT stmt,string
text,SQLINTEGER tl)
{
SQLRETURN retcode;
//uint16* utf16=UTF8toUTF16(text,null);
retcode=SQLExecDirectW(stmt,cast(SQLWCHAR*)toUTF16z(text),tl);
return retcode;
}
string[][] fetchAll(const char* pszSql)
{
string[][] v;
if(pszSql is null )
return null;
retCode=SQLExecDirectUTF8(hStmt,to!string(pszSql),SQL_NTS);
if((retCode != SQL_SUCCESS) && (retCode !=
SQL_SUCCESS_WITH_INFO))
{
throw new Exception(format("Error AllocHandle with
retCode: %d",retCode));
return null;
}
retCode=SQLNumResultCols(hStmt,&col);
if((retCode != SQL_SUCCESS) && (retCode !=
SQL_SUCCESS_WITH_INFO))
{
throw new Exception(format("Error AllocHandle with
retCode: %d",retCode));
return null;
}
row=0;
SQLINTEGER colLen = 0;
SQLSMALLINT buf_len = 0;
SQLINTEGER colType = 0;
while(true)
{
char sz_buf[256];
char* pszBuf;
SQLINTEGER buflen;
string[] rowData=new string[col+1];
if(SQLFetch(hStmt)==SQL_NO_DATA)
{
break;
}
for(int i=1;i<=colCount;i++)
{
SQLColAttribute(hStmt, cast(ushort)i, SQL_DESC_NAME,
sz_buf.ptr, 256, &buf_len, cast(void*)0);
SQLColAttribute(hStmt, cast(ushort)i, SQL_DESC_TYPE,
cast(void*)0, 0, cast(short*)0, &colType);
SQLColAttribute(hStmt, cast(ushort)i,
SQL_DESC_LENGTH, null, 0, cast(short*)0, &colLen);
pszBuf=cast(char*)(new char[colLen+1]);
//pszBuf[0]='\0';
SQLGetData(hStmt,cast(ushort)i,SQL_C_CHAR,pszBuf,50,cast(int*)&buflen);
pszBuf[buflen]='\000';
rowData[i-1]=to!string(pszBuf);
}
v~=rowData;
row++;
}
SQLCancel(hStmt);
return v;
}
string[][] fetchAll(string sql)
{
return fetchAll(sql.ptr);
}
[/code]
I've never used ODBC before, but a quick scan of the MSDN docs
suggests that you should use SQL_C_WCHAR instead, maybe using
some D wstring functions too.
BTW, convert sql.ptr -> std.string.toStringz(sql); this is good
practice, though I'm not sure it's your problem.
NMS
