Question

这是API返回的一些数据。我需要遍历嵌套结构中包含的数组。例如，在下页的savedMajorIds中：

var pg = require("pg");
var fs = require('fs');

const pool = new pg.Pool({
  user: 'smurf',
  host: 'localhost',
  database: 'mydb',
  password: 'smurf',
  port: 5432,
})

var filename = 'allCountries.txt';

var fs = require('fs'),
    es = require('event-stream');

var lineNr = 0;
var max = 11784251; // Number of line, dirty, to get % of lines inserted

// Connect to Postgresql
pool.connect((err, client, done) => {
  if (err) throw err

  // Stream file line by line
  var s = fs.createReadStream(filename)
    .pipe(es.split())
    .pipe(es.map(function(e, cb) {

        lineNr += 1;

        // Each line need to be properly formated
        e = e.split("\t"); //TAB split

        // The following fields need formating
        e[0] = parseInt(e[0]);
        e[4] = parseFloat(e[4]);
        e[5] = parseFloat(e[5]);
        e[14] = parseInt(e[14]);

        e[15] = e[15] == '' ? 0 : e[15];

        e[16] = parseInt(e[16]);

        // Insert into db
        pool.query('INSERT INTO geonames.rawdata (geonameid, name, asciiname, alternatenames, latitude, longitude, fclass, fcode, country, cc2, admin1, admin2, admin3, admin4, population, elevation, gtopo30, timezone, moddate) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15, $16, $17, $18, $19);', e, function(err, result) {
            cb(err, result); // call the callback
            console.log("Line added ", lineNr, (lineNr / max * 100) + "%") // Monitor progress
        });

    })
    .resume()
    .on('error', function(err) {
        done();
        console.log('Error while reading file.', err);
    })
    .on('end', function() {
        done();
        console.log('Read entire file.')
    })
    );
}) // END pool.connect

返回是，所以我很确定它正在寻找正确的东西。但是，当我尝试循环获取值时，它会中断。代码是：

const {Pool} = require("pg");
const {StringStream} = require("scramjet");
const fs = require("fs");

const pool = new Pool(options);
const max = 11784251;
const INSERT_ENTRY = 'INSERT INTO geonames.rawdata (geonameid, name, asciiname, alternatenames, latitude, longitude, fclass, fcode, country, cc2, admin1, admin2, admin3, admin4, population, elevation, gtopo30, timezone, moddate) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15, $16, $17, $18, $19);';

StringStream
    .from(fs.createReadStream(filename))
    .lines()
    .parse(line => {
        // Each line need to be properly formated
        const entry = line.split("\t"); //TAB split

        // The following fields need formating
        entry[0] = parseInt(entry[0]);
        entry[4] = parseFloat(entry[4]);
        entry[5] = parseFloat(entry[5]);
        entry[14] = parseInt(entry[14]);
        entry[15] = entry[15] == '' ? 0 : entry[15];
        entry[16] = parseInt(entry[16]);

        return entry;
    })
    .setOptions({maxParallel: 32})
    .each(entry => {
        const client = await pool.connect();
        try {
            await client.query(INSERT_ENTRY, entry)
        } catch(err) {
            console.log('Error while adding line...', err);
            // some more logic could be here?
        } finally {
            client.release();
        }
    })
    .each(() => !(lineNr++ % 1000) && console.log("Line added ", lineNr, (lineNr / max * 100) + "%"))
    .run()
    .then(
        () => console.log('Read entire file.'), 
        e => console.log('Error while handling file.', err)
    );

错误日志不喜欢arrayLen（）部分，但到目前为止，我一直无法使它起作用。

Answer 1

对于任何偶然发现此问题的人：

(i=1, i < arrayLen(apiprofile.result.savedMajorIds),i=i+1)

需要成为

(i=1; i < arrayLen(apiprofile.result.savedMajorIds); i=i+1)

或

(i=1; i < arrayLen(apiprofile.result.savedMajorIds); i++)

Answer 2

以下是一些选项，具体取决于您的ColdFusion版本。

if (isArray(apiprofile.result.savedMajorIDs)) {
    // For/In Loop on Array - Possibly CF9, Definitely CF10+ (Verify version) 
    // Note: x will leak unless var'ed inside function.
    for ( x IN apiprofile.result.savedMajorIDs ) {
        writeoutput( x & "<br>" ) ;
    }

    // ArrayEach - CF10+ > Note: y will not leak.
    ArrayEach(apiprofile.result.savedMajorIDs, function(y){writeoutput(y & "<br>");}) ;

    // Member Function .each() - CF11+  > Note: z will not leak.
    apiprofile.result.savedMajorIDs.each( function(z){writeoutput(z & "<br>");}) ;
}

https://trycf.com/gist/f6f3e64635e4b72da15521a3d49d485f/acf11?theme=monokai

循环嵌套在结构内的数组

2 个答案: