c-treeDB API for C++ - Developers Guide

Reading and writing field data to a record buffer

The c-treeDB CTRecord class has the following methods to read field data from the record buffer:

Function name	Explanation
GetFieldAsBool	Read field data as Boolean value
GetFieldAsSigned	Read field data as signed integer value
GetFieldAsUnsigned	Read field data as unsigned integer value
GetFieldAsDate	Read field data as date value
GetFieldAsTime	Read field data as time value
GetFieldAsMoney	Read field data as money value
GetFieldAsFloat	Read field data as double value
GetFieldAsDateTime	Read field data as time stamp value
GetFieldAsString	Read field data as string value
GetFieldAsBinary	Read field data as binary data
GetFieldAsBlob	Read field data as blob
GetFieldAsBigint	Read field data as signed 64 bit integer
GetFieldAsCurrency	Read field data as currency value
GetFieldAsNumber	Read field data as number (BCD) value

// display all field data on screen

void DisplayData(CTTable &ATable, CTRecord &ARecord)

{

NINT count = ATable.GetFieldCount();

NINT i;

CTString str;

for (i = 0; i < count; i++)

{

ARecord.GetFieldAsString(i, str);

printf("Field %d: %s\n", i, str.c_str());

}

}

The following functions should be used to write fields into the data record buffer:

Function	Explanation
SetFieldAsBool	update field data as Boolean value
SetFieldAsSigned	update field data as signed integer value
SetFieldAsUnsigned	update field data as unsigned integer value
SetFieldAsDate	update field data as date value
SetFieldAsTime	update field data as time value
SetFieldAsMoney	update field data as money value
SetFieldAsFloat	update field data as double value
SetFieldAsDateTime	update field data as time stamp value
SetFieldAsString	update field data as string value
SetFieldAsBinary	update field data as binary data
SetFieldAsBlob	update field data as blob
SetFieldAsBigint	update field data as signed 64 bit integer
SetFieldAsCurrency	update field data as currency value
SetFieldAsNumber	Read field data as number (BCD) value

// add new record

void AddRecord(CTRecord &ARecord, const CTString& name, const CTString& address, const CTString& phone)

{

// clear the record buffer

ARecord.Clear();

// populate the record buffer with field data

ARecord.SetFieldAsString(0, name);

ARecord.SetFieldAsString(1, address);

ARecord.SetFieldAsString(2, phone);

// add the new record

ARecord.Write();

}

The SetFieldAs...() methods will also clear the null bit flag for the updated field.

When you invoke one of the GetFieldAs...() or SetFieldAs...() methods, you pass the field number or field name and the data you want to read from or write to the data record buffer.

If the type of the field you are trying to read from, or write to, is different to the type of the data specified by the GetFieldAs...() or SetFieldAs...() methods, the record manager will automatically convert the field data type to match the data type of the parameter of passed by one of the GetFieldAs...() or SetFieldAs...() method.

For example, if you are writing a report generator application that displays the fields of a record on screen, you can read all fields in the record buffer with GetFieldAsString() and the record manager will convert the different field types to string. Boolean field type is converted as "True" or "False", numeric values are converted to string and dates and times use the session wide default date and time formats.