func (dt *DbfTable) getNormalizedFieldName(name string) (s string) {
e := mahonia.NewEncoder(dt.fileEncoding)
b := []byte(e.ConvertString(name))
if len(b) > 10 {
b = b[0:10]
}
d := mahonia.NewDecoder(dt.fileEncoding)
s = d.ConvertString(string(b))
return
}
func (dt *DbfTable) FieldValue(row int, fieldIndex int) (value string) {
// create decoder to convert bytes to utf-8
d := mahonia.NewDecoder(dt.fileEncoding)
offset := int(dt.numberOfBytesInHeader)
lengthOfRecord := int(dt.lengthOfEachRecord)
offset = offset + (row * lengthOfRecord)
recordOffset := 1
for i := 0; i < len(dt.fields); i++ {
if i == fieldIndex {
break
} else {
recordOffset += int(dt.fields[i].fieldLength)
}
}
temp := dt.dataStore[(offset + recordOffset):((offset + recordOffset) + int(dt.fields[fieldIndex].fieldLength))]
for i := 0; i < len(temp); i++ {
if temp[i] == 0x00 {
temp = temp[0:i]
break
}
}
s := d.ConvertString(string(temp))
//fmt.Printf("utf-8 value:[%#v]\n", s)
value = strings.TrimSpace(s)
//fmt.Printf("raw value:[%#v]\n", dt.dataStore[(offset + recordOffset):((offset + recordOffset) + int(dt.Fields[fieldIndex].fieldLength))])
//fmt.Printf("utf-8 value:[%#v]\n", []byte(s))
//value = string(dt.dataStore[(offset + recordOffset):((offset + recordOffset) + int(dt.Fields[fieldIndex].fieldLength))])
return
}
func NewFromFile(fileName string, fileEncoding string) (table *DbfTable, err error) {
// create a decoder to decode file correctly
d := mahonia.NewDecoder(fileEncoding)
s, err := readFile(fileName)
if err != nil {
return nil, err
}
// Create and pupulate DbaseTable struct
dt := new(DbfTable)
dt.fileEncoding = fileEncoding
// read dbase table header information
dt.fileSignature = s[0]
dt.updateYear = s[1]
dt.updateMonth = s[2]
dt.updateDay = s[3]
dt.numberOfRecords = uint32(s[4]) | (uint32(s[5]) << 8) | (uint32(s[6]) << 16) | (uint32(s[7]) << 24)
dt.numberOfBytesInHeader = uint16(s[8]) | (uint16(s[9]) << 8)
dt.lengthOfEachRecord = uint16(s[10]) | (uint16(s[11]) << 8)
// create fieldMap to taranslate field name to index
dt.fieldMap = make(map[string]int)
// Number of fields in dbase table
dt.numberOfFields = int((dt.numberOfBytesInHeader - 1 - 32) / 32)
// populate dbf fields
for i := 0; i < int(dt.numberOfFields); i++ {
offset := (i * 32) + 32
fieldName := strings.Trim(d.ConvertString(string(s[offset:offset+10])), string([]byte{0}))
dt.fieldMap[fieldName] = i
var err error
switch s[offset+11] {
case 'C':
err = dt.AddTextField(fieldName, s[offset+16])
case 'N':
err = dt.AddNumberField(fieldName, s[offset+16])
case 'F':
err = dt.AddFloatField(fieldName, s[offset+16])
case 'L':
err = dt.AddBooleanField(fieldName)
case 'D':
err = dt.AddDateField(fieldName)
}
// Check return value for errors
if err != nil {
return nil, err
}
//fmt.Printf("Field name:%v\n", fieldName)
//fmt.Printf("Field data type:%v\n", string(s[offset+11]))
//fmt.Printf("Field length:%v\n", s[offset+16])
//fmt.Println("-----------------------------------------------")
}
//fmt.Printf("DbfReader:\n%#v\n", dt)
//fmt.Printf("DbfReader:\n%#v\n", int(dt.Fields[2].fieldLength))
//fmt.Printf("num records in table:%v\n", (dt.numberOfRecords))
//fmt.Printf("lenght of each record:%v\n", (dt.lengthOfEachRecord))
// Since we are reading dbase file from the disk at least at this
// phase changing schema of dbase file is not allowed.
dt.dataEntryStarted = true
// set DbfTable dataStore slice that will store the complete file in memory
dt.dataStore = s
return dt, nil
}