我可以在哪里找到一些JavaScript代码来解析CSV数据?
当前回答
只是随便说说而已。我最近遇到了用Javascript解析CSV列的需求,于是我选择了自己的简单解决方案。它满足了我的需要,也可能帮助到其他人。
const csvString = '"Some text, some text",,"",true,false,"more text","more,text, more, text ",true'; const parseCSV = text => { const lines = text.split('\n'); const output = []; lines.forEach(line => { line = line.trim(); if (line.length === 0) return; const skipIndexes = {}; const columns = line.split(','); output.push(columns.reduce((result, item, index) => { if (skipIndexes[index]) return result; if (item.startsWith('"') && !item.endsWith('"')) { while (!columns[index + 1].endsWith('"')) { index++; item += `,${columns[index]}`; skipIndexes[index] = true; } index++; skipIndexes[index] = true; item += `,${columns[index]}`; } result.push(item); return result; }, [])); }); return output; }; console.log(parseCSV(csvString));
其他回答
我有一个实现作为电子表格项目的一部分。
此代码尚未经过全面测试,但欢迎任何人使用它。
正如一些答案所指出的那样,如果您实际上有DSV或TSV文件,您的实现可以简单得多,因为它们不允许在值中使用记录和字段分隔符。另一方面,CSV实际上可以在字段中使用逗号和换行符,这打破了大多数正则表达式和基于分割的方法。
var CSV = {
parse: function(csv, reviver) {
reviver = reviver || function(r, c, v) { return v; };
var chars = csv.split(''), c = 0, cc = chars.length, start, end, table = [], row;
while (c < cc) {
table.push(row = []);
while (c < cc && '\r' !== chars[c] && '\n' !== chars[c]) {
start = end = c;
if ('"' === chars[c]){
start = end = ++c;
while (c < cc) {
if ('"' === chars[c]) {
if ('"' !== chars[c+1]) {
break;
}
else {
chars[++c] = ''; // unescape ""
}
}
end = ++c;
}
if ('"' === chars[c]) {
++c;
}
while (c < cc && '\r' !== chars[c] && '\n' !== chars[c] && ',' !== chars[c]) {
++c;
}
} else {
while (c < cc && '\r' !== chars[c] && '\n' !== chars[c] && ',' !== chars[c]) {
end = ++c;
}
}
row.push(reviver(table.length-1, row.length, chars.slice(start, end).join('')));
if (',' === chars[c]) {
++c;
}
}
if ('\r' === chars[c]) {
++c;
}
if ('\n' === chars[c]) {
++c;
}
}
return table;
},
stringify: function(table, replacer) {
replacer = replacer || function(r, c, v) { return v; };
var csv = '', c, cc, r, rr = table.length, cell;
for (r = 0; r < rr; ++r) {
if (r) {
csv += '\r\n';
}
for (c = 0, cc = table[r].length; c < cc; ++c) {
if (c) {
csv += ',';
}
cell = replacer(r, c, table[r][c]);
if (/[,\r\n"]/.test(cell)) {
cell = '"' + cell.replace(/"/g, '""') + '"';
}
csv += (cell || 0 === cell) ? cell : '';
}
}
return csv;
}
};
下面是我的PEG(.js)语法,它在RFC 4180中似乎做得不错(即它处理http://en.wikipedia.org/wiki/Comma-separated_values):上的示例)
start
= [\n\r]* first:line rest:([\n\r]+ data:line { return data; })* [\n\r]* { rest.unshift(first); return rest; }
line
= first:field rest:("," text:field { return text; })*
& { return !!first || rest.length; } // ignore blank lines
{ rest.unshift(first); return rest; }
field
= '"' text:char* '"' { return text.join(''); }
/ text:[^\n\r,]* { return text.join(''); }
char
= '"' '"' { return '"'; }
/ [^"]
在http://jsfiddle.net/knvzk/10或http://pegjs.majda.cz/online上试试吧。从https://gist.github.com/3362830下载生成的解析器。
只是随便说说而已。我最近遇到了用Javascript解析CSV列的需求,于是我选择了自己的简单解决方案。它满足了我的需要,也可能帮助到其他人。
const csvString = '"Some text, some text",,"",true,false,"more text","more,text, more, text ",true'; const parseCSV = text => { const lines = text.split('\n'); const output = []; lines.forEach(line => { line = line.trim(); if (line.length === 0) return; const skipIndexes = {}; const columns = line.split(','); output.push(columns.reduce((result, item, index) => { if (skipIndexes[index]) return result; if (item.startsWith('"') && !item.endsWith('"')) { while (!columns[index + 1].endsWith('"')) { index++; item += `,${columns[index]}`; skipIndexes[index] = true; } index++; skipIndexes[index] = true; item += `,${columns[index]}`; } result.push(item); return result; }, [])); }); return output; }; console.log(parseCSV(csvString));
我已经构造了这个JavaScript脚本来解析字符串到数组对象中的CSV。我发现最好将整个CSV分解成行、字段并相应地处理它们。我认为这将使您更容易更改代码以满足您的需要。
//
//
// CSV to object
//
//
const new_line_char = '\n';
const field_separator_char = ',';
function parse_csv(csv_str) {
var result = [];
let line_end_index_moved = false;
let line_start_index = 0;
let line_end_index = 0;
let csr_index = 0;
let cursor_val = csv_str[csr_index];
let found_new_line_char = get_new_line_char(csv_str);
let in_quote = false;
// Handle \r\n
if (found_new_line_char == '\r\n') {
csv_str = csv_str.split(found_new_line_char).join(new_line_char);
}
// Handle the last character is not \n
if (csv_str[csv_str.length - 1] !== new_line_char) {
csv_str += new_line_char;
}
while (csr_index < csv_str.length) {
if (cursor_val === '"') {
in_quote = !in_quote;
} else if (cursor_val === new_line_char) {
if (in_quote === false) {
if (line_end_index_moved && (line_start_index <= line_end_index)) {
result.push(parse_csv_line(csv_str.substring(line_start_index, line_end_index)));
line_start_index = csr_index + 1;
} // Else: just ignore line_end_index has not moved or line has not been sliced for parsing the line
} // Else: just ignore because we are in a quote
}
csr_index++;
cursor_val = csv_str[csr_index];
line_end_index = csr_index;
line_end_index_moved = true;
}
// Handle \r\n
if (found_new_line_char == '\r\n') {
let new_result = [];
let curr_row;
for (var i = 0; i < result.length; i++) {
curr_row = [];
for (var j = 0; j < result[i].length; j++) {
curr_row.push(result[i][j].split(new_line_char).join('\r\n'));
}
new_result.push(curr_row);
}
result = new_result;
}
return result;
}
function parse_csv_line(csv_line_str) {
var result = [];
//let field_end_index_moved = false;
let field_start_index = 0;
let field_end_index = 0;
let csr_index = 0;
let cursor_val = csv_line_str[csr_index];
let in_quote = false;
// Pretend that the last char is the separator_char to complete the loop
csv_line_str += field_separator_char;
while (csr_index < csv_line_str.length) {
if (cursor_val === '"') {
in_quote = !in_quote;
} else if (cursor_val === field_separator_char) {
if (in_quote === false) {
if (field_start_index <= field_end_index) {
result.push(parse_csv_field(csv_line_str.substring(field_start_index, field_end_index)));
field_start_index = csr_index + 1;
} // Else: just ignore field_end_index has not moved or field has not been sliced for parsing the field
} // Else: just ignore because we are in quote
}
csr_index++;
cursor_val = csv_line_str[csr_index];
field_end_index = csr_index;
field_end_index_moved = true;
}
return result;
}
function parse_csv_field(csv_field_str) {
with_quote = (csv_field_str[0] === '"');
if (with_quote) {
csv_field_str = csv_field_str.substring(1, csv_field_str.length - 1); // remove the start and end quotes
csv_field_str = csv_field_str.split('""').join('"'); // handle double quotes
}
return csv_field_str;
}
// Initial method: check the first newline character only
function get_new_line_char(csv_str) {
if (csv_str.indexOf('\r\n') > -1) {
return '\r\n';
} else {
return '\n'
}
}
csvToArray v1.3
一个紧凑(645字节),但兼容的函数,将CSV字符串转换为2D数组,符合RFC4180标准。
https://code.google.com/archive/p/csv-to-array/downloads
常用用法:jQuery
$.ajax({
url: "test.csv",
dataType: 'text',
cache: false
}).done(function(csvAsString){
csvAsArray=csvAsString.csvToArray();
});
常用用法:JavaScript
csvAsArray = csvAsString.csvToArray();
覆盖字段分隔符
csvAsArray = csvAsString.csvToArray("|");
覆盖记录分离器
csvAsArray = csvAsString.csvToArray("", "#");
覆盖跳过报头
csvAsArray = csvAsString.csvToArray("", "", 1);
覆盖所有
csvAsArray = csvAsString.csvToArray("|", "#", 1);
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