Mixing
Understanding Papaparse with local file
I am trying to understand how to properly implement Papaparse with a local file. I have looked at a lot of online resources, and the approach they take is this
loadTextFromFile (event) {
if (!event.target.files[0]) {
alert('Upload a file.')
} else {
let file = event.target.files[0];
if (file) {
let reader = new FileReader();
let config = {
delimiter: "",
newline: "",
quoteChar: '"',
escapeChar: '"',
header: true,
trimHeaders: false
};
reader.onload = e => this.$emit('load', Papa.parse(event.target.result, config));
reader.onload = function (event) {
let results = Papa.parse(event.target.result, config);
console.log('PAPA RESULT: ', results.data);
console.log('ROWS:', event.target.result);
};
reader.readAsText(file);
} else {
alert('Please select a file to upload.')
}
}
}
So they use a FileReader and it doesnt seem to load the file until the end within readAsText. However, the above example works perfectly, although I still need to fully understand the code.
Then there are other examples, which seem to do it without a FileReader
loadTextFromFile (event) {
if (!event.target.files[0]) {
alert('Upload a file.')
} else {
let file = event.target.files[0];
if (file) {
Papa.parse(file, {
header: true,
dynamicTyping: true,
complete: function(results) {
console.log(results.data)
}
});
} else {
alert('Please select a file to upload.')
}
}
}
Once again, this works perfectly. So what I am trying to understand is why do people sometimes use the FileReader, and perhaps an explanation as to what exactly is happening in the first example.
What option should I be using?
Thanks
javascript papaparse
asked Jan 2 at 19:50
kate_hudsonkate_hudson
71532138
add a comment |
I am trying to understand how to properly implement Papaparse with a local file. I have looked at a lot of online resources, and the approach they take is this
loadTextFromFile (event) {
if (!event.target.files[0]) {
alert('Upload a file.')
} else {
let file = event.target.files[0];
if (file) {
let reader = new FileReader();
let config = {
delimiter: "",
newline: "",
quoteChar: '"',
escapeChar: '"',
header: true,
trimHeaders: false
};
reader.onload = e => this.$emit('load', Papa.parse(event.target.result, config));
reader.onload = function (event) {
let results = Papa.parse(event.target.result, config);
console.log('PAPA RESULT: ', results.data);
console.log('ROWS:', event.target.result);
};
reader.readAsText(file);
} else {
alert('Please select a file to upload.')
}
}
}
So they use a FileReader and it doesnt seem to load the file until the end within readAsText. However, the above example works perfectly, although I still need to fully understand the code.
Then there are other examples, which seem to do it without a FileReader
loadTextFromFile (event) {
if (!event.target.files[0]) {
alert('Upload a file.')
} else {
let file = event.target.files[0];
if (file) {
Papa.parse(file, {
header: true,
dynamicTyping: true,
complete: function(results) {
console.log(results.data)
}
});
} else {
alert('Please select a file to upload.')
}
}
}
Once again, this works perfectly. So what I am trying to understand is why do people sometimes use the FileReader, and perhaps an explanation as to what exactly is happening in the first example.
What option should I be using?
Thanks
javascript papaparse
asked Jan 2 at 19:50
kate_hudsonkate_hudson
71532138
add a comment |
I am trying to understand how to properly implement Papaparse with a local file. I have looked at a lot of online resources, and the approach they take is this
loadTextFromFile (event) {
if (!event.target.files[0]) {
alert('Upload a file.')
} else {
let file = event.target.files[0];
if (file) {
let reader = new FileReader();
let config = {
delimiter: "",
newline: "",
quoteChar: '"',
escapeChar: '"',
header: true,
trimHeaders: false
};
reader.onload = e => this.$emit('load', Papa.parse(event.target.result, config));
reader.onload = function (event) {
let results = Papa.parse(event.target.result, config);
console.log('PAPA RESULT: ', results.data);
console.log('ROWS:', event.target.result);
};
reader.readAsText(file);
} else {
alert('Please select a file to upload.')
}
}
}
So they use a FileReader and it doesnt seem to load the file until the end within readAsText. However, the above example works perfectly, although I still need to fully understand the code.
Then there are other examples, which seem to do it without a FileReader
loadTextFromFile (event) {
if (!event.target.files[0]) {
alert('Upload a file.')
} else {
let file = event.target.files[0];
if (file) {
Papa.parse(file, {
header: true,
dynamicTyping: true,
complete: function(results) {
console.log(results.data)
}
});
} else {
alert('Please select a file to upload.')
}
}
}
Once again, this works perfectly. So what I am trying to understand is why do people sometimes use the FileReader, and perhaps an explanation as to what exactly is happening in the first example.
What option should I be using?
Thanks
javascript papaparse
asked Jan 2 at 19:50
kate_hudsonkate_hudson
71532138
I am trying to understand how to properly implement Papaparse with a local file. I have looked at a lot of online resources, and the approach they take is this
loadTextFromFile (event) {
if (!event.target.files[0]) {
alert('Upload a file.')
} else {
let file = event.target.files[0];
if (file) {
let reader = new FileReader();
let config = {
delimiter: "",
newline: "",
quoteChar: '"',
escapeChar: '"',
header: true,
trimHeaders: false
};
reader.onload = e => this.$emit('load', Papa.parse(event.target.result, config));
reader.onload = function (event) {
let results = Papa.parse(event.target.result, config);
console.log('PAPA RESULT: ', results.data);
console.log('ROWS:', event.target.result);
};
reader.readAsText(file);
} else {
alert('Please select a file to upload.')
}
}
}
So they use a FileReader and it doesnt seem to load the file until the end within readAsText. However, the above example works perfectly, although I still need to fully understand the code.
Then there are other examples, which seem to do it without a FileReader
loadTextFromFile (event) {
if (!event.target.files[0]) {
alert('Upload a file.')
} else {
let file = event.target.files[0];
if (file) {
Papa.parse(file, {
header: true,
dynamicTyping: true,
complete: function(results) {
console.log(results.data)
}
});
} else {
alert('Please select a file to upload.')
}
}
}
Once again, this works perfectly. So what I am trying to understand is why do people sometimes use the FileReader, and perhaps an explanation as to what exactly is happening in the first example.
What option should I be using?
Thanks
javascript papaparse
javascript papaparse
asked Jan 2 at 19:50
kate_hudsonkate_hudson
71532138
asked Jan 2 at 19:50
kate_hudsonkate_hudson
71532138
asked Jan 2 at 19:50
kate_hudsonkate_hudson
71532138
asked Jan 2 at 19:50
kate_hudsonkate_hudson
71532138
asked Jan 2 at 19:50
kate_hudsonkate_hudson
71532138
71532138
add a comment |
add a comment |
1 Answer
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It looks like the first example doesn't really make sense -- they're assigning reader.onload twice, so the first assignment that does the $emit thing isn't even used.
I would say that the first example is a bit sloppy and unnecessary. The only reasons that jump to mind for using your own FileReader are:
- A desire to learn how to use the FileReader API,
- A need to customize the FileReader for some reason
- Wanting to time how long it takes to load the file vs. how long it takes Papa to parse the content
I would mostly ignore the first example, and stick to the examples in Papa's documentation which are cleaner and simpler.
answered Jan 2 at 22:19
MattMatt
12.8k95497
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
It looks like the first example doesn't really make sense -- they're assigning reader.onload twice, so the first assignment that does the $emit thing isn't even used.
I would say that the first example is a bit sloppy and unnecessary. The only reasons that jump to mind for using your own FileReader are:
- A desire to learn how to use the FileReader API,
- A need to customize the FileReader for some reason
- Wanting to time how long it takes to load the file vs. how long it takes Papa to parse the content
I would mostly ignore the first example, and stick to the examples in Papa's documentation which are cleaner and simpler.
answered Jan 2 at 22:19
MattMatt
12.8k95497
add a comment |
It looks like the first example doesn't really make sense -- they're assigning reader.onload twice, so the first assignment that does the $emit thing isn't even used.
I would say that the first example is a bit sloppy and unnecessary. The only reasons that jump to mind for using your own FileReader are:
- A desire to learn how to use the FileReader API,
- A need to customize the FileReader for some reason
- Wanting to time how long it takes to load the file vs. how long it takes Papa to parse the content
I would mostly ignore the first example, and stick to the examples in Papa's documentation which are cleaner and simpler.
answered Jan 2 at 22:19
MattMatt
12.8k95497
add a comment |
It looks like the first example doesn't really make sense -- they're assigning reader.onload twice, so the first assignment that does the $emit thing isn't even used.
I would say that the first example is a bit sloppy and unnecessary. The only reasons that jump to mind for using your own FileReader are:
- A desire to learn how to use the FileReader API,
- A need to customize the FileReader for some reason
- Wanting to time how long it takes to load the file vs. how long it takes Papa to parse the content
I would mostly ignore the first example, and stick to the examples in Papa's documentation which are cleaner and simpler.
answered Jan 2 at 22:19
MattMatt
12.8k95497
It looks like the first example doesn't really make sense -- they're assigning reader.onload twice, so the first assignment that does the $emit thing isn't even used.
I would say that the first example is a bit sloppy and unnecessary. The only reasons that jump to mind for using your own FileReader are:
- A desire to learn how to use the FileReader API,
- A need to customize the FileReader for some reason
- Wanting to time how long it takes to load the file vs. how long it takes Papa to parse the content
I would mostly ignore the first example, and stick to the examples in Papa's documentation which are cleaner and simpler.
answered Jan 2 at 22:19
MattMatt
12.8k95497
answered Jan 2 at 22:19
MattMatt
12.8k95497
answered Jan 2 at 22:19
MattMatt
12.8k95497
answered Jan 2 at 22:19
MattMatt
12.8k95497
12.8k95497
add a comment |
add a comment |
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