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javascriptjsonobjectproperties

Unable to access JavaScript Object property from CSV file

I am having a hard time figuring out how to access a property of my javascript object.

I have a Node JS application that downloads a CSV file from the WHO with covid data and then I loop through each of these entries. Here is how I loop through each of the CSV entries:

fs.createReadStream("data.csv")
.pipe(csv())
.on("data", (data) => {
  //process data 
})
.on("end", () => {
});

Here is one sample of the output when I run console.log(data)

{                                                                         
  'Name': 'Niger',                                                       
  'WHO Region': 'Africa',                                                 
  'Cases - cumulative total': '6203',                                     
  'Cases - cumulative total per 100000 population': '25.63',              
  'Cases - newly reported in last 7 days': '64',                          
  'Cases - newly reported in last 7 days per 100000 population': '0.26',  
  'Cases - newly reported in last 24 hours': '10',                        
  'Deaths - cumulative total': '205',                                     
  'Deaths - cumulative total per 100000 population': '0.85',              
  'Deaths - newly reported in last 7 days': '1',                          
  'Deaths - newly reported in last 7 days per 100000 population': '0',    
  'Deaths - newly reported in last 24 hours': '0'                         
}

If I run typeof data I am getting object.

I would like to access some properties of this object. If I output data["WHO Region"] I get "Africa". So this works.

However, I am unable to access the name of those object.

console.log(data["Name"]);
console.log(data.hasOwnProperty("Name"));

Outputs respectively undefined and false

Even though the name property is present within the object.

I have also tried to list the keys of the object with Object.keys(data) and here is the result:

 [ 'Name', 'WHO Region', 'Cases - cumulative total', ... ]

So apparently the key Name does exist but I can't access it for some reason. Am I missing something there?

Solution

  • The issue is caused by the Byte Order Mark (BOM) at the start of the file, represented by the byte sequence 0xEF,0xBB,0xBF corresponding to the UTF-8 codepoint U+FEFF.

    enter image description here

    An easy workaround for your code would be to replace this like so:

    const results = [];

fs.createReadStream('data.csv')
.pipe(csv())
.on('data', (data) => {
    // Replace BOM in key
    const key1 = Object.keys(data)[0];
    data = { ...data, [key1.replace(/\uFEFF/, '')]: data[key1] };
    results.push(data);
})
.on('end', () => {
    results.forEach(result => { 
        console.log(`Name: ${result["Name"]}`);
    })
});

    or

    You could open the file in Notepad++ and using the Encoding menu change it from UTF-8-BOM to UTF-8 and saving.