Documentation
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Overview ¶
Package csv reads and writes comma-separated values (CSV) files. There are many kinds of CSV files; this package supports the format described in RFC 4180.
A csv file contains zero or more records of one or more fields per record. Each record is separated by the newline character. The final record may optionally be followed by a newline character.
field1,field2,field3
White space is considered part of a field.
Carriage returns before newline characters are silently removed.
Blank lines are ignored. A line with only whitespace characters (excluding the ending newline character) is not considered a blank line.
Fields which start and stop with the quote character " are called quoted-fields. The beginning and ending quote are not part of the field.
The source:
normal string,"quoted-field"
results in the fields
{`normal string`, `quoted-field`}
Within a quoted-field a quote character followed by a second quote character is considered a single quote.
"the ""word"" is true","a ""quoted-field"""
results in
{`the "word" is true`, `a "quoted-field"`}
Newlines and commas may be included in a quoted-field
"Multi-line field","comma is ,"
results in
{`Multi-line
field`, `comma is ,`}
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
var ( ErrTrailingComma = errors.New("extra delimiter at end of line") // Deprecated: No longer used. ErrBareQuote = errors.New("bare \" in non-quoted-field") ErrQuote = errors.New("extraneous or missing \" in quoted-field") ErrFieldCount = errors.New("wrong number of fields") )
These are the errors that can be returned in ParseError.Err.
Functions ¶
This section is empty.
Types ¶
type ParseError ¶
type ParseError struct {
StartLine int // Line where the record starts
Line int // Line where the error occurred
Column int // Column (1-based byte index) where the error occurred
Err error // The actual error
}
A ParseError is returned for parsing errors. Line numbers are 1-indexed and columns are 0-indexed.
func (*ParseError) Error ¶
func (e *ParseError) Error() string
func (*ParseError) Unwrap ¶ added in go1.13
func (e *ParseError) Unwrap() error
type Reader ¶
type Reader struct {
// Comma is the field delimiter.
// It is set to comma (',') by NewReader.
// Comma must be a valid rune and must not be \r, \n,
// or the Unicode replacement character (0xFFFD).
Comma rune
// 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
// FieldsPerRecord is the number of expected fields per record.
// If FieldsPerRecord is positive, Read requires each record to
// have the given number of fields. If FieldsPerRecord is 0, Read sets it to
// the number of fields in the first record, so that future records must
// have the same field count. If FieldsPerRecord is negative, no check is
// made and records may have a variable number of fields.
FieldsPerRecord int
// If LazyQuotes is true, a quote may appear in an unquoted field and a
// non-doubled quote may appear in a quoted field.
LazyQuotes bool
// If TrimLeadingSpace is true, leading white space in a field is ignored.
// This is done even if the field delimiter, Comma, is white space.
TrimLeadingSpace bool
// ReuseRecord controls whether calls to Read may return a slice sharing
// the backing array of the previous call's returned slice for performance.
// By default, each call to Read returns newly allocated memory owned by the caller.
ReuseRecord bool
TrailingComma bool // Deprecated: No longer used.
// contains filtered or unexported fields
}
A Reader reads records from a CSV-encoded file.
As returned by NewReader, a Reader expects input conforming to