README
¶
CSV
A Go CSV implementation
inspired by Python's CSV module.
It supports various CSV dialects (see below) and is fully backward compatible
with the encoding/csv package in the
Go standard library.
Examples
Here's a basic writing example:
f, err := os.Create("output.csv")
checkError(err)
defer func() {
err := f.Close()
checkError(err)
}
w := NewWriter(f)
w.Write([]string{
"a",
"b",
"c",
})
w.Flush()
// output.csv will now contains the line "a b c" with a trailing newline.
Here's a basic reading example:
f, err := os.Open('myfile.csv')
checkError(err)
defer func() {
err := f.Close()
checkError(err)
}
r := NewReader(f)
for {
fields, err := r.Read()
if err == io.EOF {
break
}
checkOtherErrors(err)
handleFields(fields)
}
CSV dialects
To modify CSV dialect, have a look at csv.Dialect,
csv.NewDialectWriter(...) and csv.NewDialectReader(...). It supports
changing:
- separator/delimiter.
- quoting modes:
- Always quote.
- Never quote.
- Quote when needed (minimal quoting).
- Quote all non-numerical fields.
- Quote all non-empty, non-numerical fields.
- line terminator.
- how quote character escaping should be done - using double escape, or using a custom escape character.
Have a look at the
documentation in csv_test.go
for example on how to use these. All values above have sane defaults (that
makes the module behave the same as the csv module in the Go standard library).
Documentation
Package documentation can be found here.
Why was this developed?
I needed it for mysqlcsvdump to
support variations of CSV output. The csv module in the Go (1.2) standard
library was inadequate as it it does not support any CSV dialect modifications
except changing separator and partially line termination.
Who developed this?
I'm Jens Rantil. Have a look at my blog for more info on what I'm working on.
Documentation
¶
Overview ¶
A CSV implementation inspired by Python's CSV module. Supports custom CSV formats.
Example (ReadingWriting) ¶
buf := bytes.Buffer{}
writer := csv.NewWriter(&buf)
writer.Write([]string{"Hello", "World", "!"})
writer.Flush()
reader := csv.NewReader(&buf)
columns, err := reader.Read()
if err != nil {
panic(err)
}
for _, s := range columns {
fmt.Println(s)
}
Output: Hello World !
Index ¶
Examples ¶
Constants ¶
const ( QuoteDefault QuoteMode = iota // See DefaultQuoting. QuoteAll = iota // Quotes around every field. QuoteMinimal = iota // Quotes when needed. QuoteNonNumeric = iota // Quotes around non-numeric fields. QuoteNonNumericNonEmpty = iota // Quotes around non-numeric or empty fields. // Never quote. Use with care. Could make things unparsable. QuoteNone = iota )
Values QuoteMode can take.
const ( DoubleQuoteDefault DoubleQuoteMode = iota // See DefaultDoubleQuote. DoDoubleQuote = iota // Escape using double escape characters. NoDoubleQuote = iota // Escape using escape character. )
Values DoubleQuoteMode can take.
const ( DefaultDelimiter = ',' DefaultQuoting = QuoteMinimal DefaultDoubleQuote = DoDoubleQuote DefaultEscapeChar = '\\' DefaultQuoteChar = '"' DefaultLineTerminator = "\n" DefaultComment = '#' )
Default dialect.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Dialect ¶
type Dialect struct {
// The delimiter that separates each field from another. Defaults to
// DefaultDelimiter.
Delimiter rune
// What quoting mode to use. Defaults to DefaultQuoting.
Quoting QuoteMode
// How to escape quotes. Defaults to DefaultDoubleQuote.
DoubleQuote DoubleQuoteMode
// Character to use for escaping. Only used if DoubleQuote==NoDoubleQuote.
// Defaults to DefaultEscapeChar.
EscapeChar rune
// Character to use as quotation mark around quoted fields. Defaults to
// DefaultQuoteChar.
QuoteChar rune
// String that separates each record in a CSV file. Defaults to
// DefaultLineTerminator.
LineTerminator string
// Comment, if not 0, is the comment character. Lines beginning with the
// Comment character without preceding whitespace are ignored.
// With leading whitespace the Comment character becomes part of the
// field, even if TrimLeadingSpace is true.
// Comment must be a valid rune and must not be \r, \n,
// or the Unicode replacement character (0xFFFD).
// It must also not be equal to Comma.
Comment rune
}
A Dialect specifies the format of a CSV file. This structure is used by a Reader or Writer to know how to operate on the file they are reading/writing.
type DoubleQuoteMode ¶
type DoubleQuoteMode int
DoubleQuoteMode defined how quote excaping should be done.
type Reader ¶
type Reader struct {
// contains filtered or unexported fields
}
A Reader reads records from a CSV-encoded file.
Can be created by calling either NewReader or using NewDialectReader.
func NewDialectReader ¶
Create a custom CSV reader.
func NewReader ¶
Creates a reader that conforms to RFC 4180 and behaves identical as a encoding/csv.Reader.
See `Default*` constants for default dialect used.
func (*Reader) Read ¶
Read reads one record from r. The record is a slice of strings with each string representing one field.
type Writer ¶
type Writer struct {
// contains filtered or unexported fields
}
A Writer writes records to a CSV encoded file.
Can be created by calling either NewWriter or using NewDialectWriter.
func NewDialectWriter ¶
Create a custom CSV writer.
func NewWriter ¶
Create a writer that conforms to RFC 4180 and behaves identical as a encoding/csv.Reader.
See `Default*` constants for default dialect used.
func (Writer) Flush ¶
func (w Writer) Flush()
Flush writes any buffered data to the underlying io.Writer. To check if an error occurred during the Flush, call Error.
Source Files
Directories
¶
| Path | Synopsis |
|---|---|
|
Helpers that makes it easy to build CSV dialects.
|
Helpers that makes it easy to build CSV dialects. |
|
Interfaces shared among go-csv and the Go standard library's encoding/csv.
|
Interfaces shared among go-csv and the Go standard library's encoding/csv. |