Author: John Au-Yeung

Sometimes, we want to force a line break on a JavaScript concatenated string.

In this article, we’ll look at how to force a line break on a JavaScript concatenated string.

How to force a line break on a JavaScript concatenated string?

To force a line break on a JavaScript concatenated string, we add the '\n' string.

For instance, we write

document.getElementById("address_box").value =
  title + "\n" + address + "\n" + address2 + "\n" + address3 + "\n" + address4;

to put a new line between each string variable with '\n'.

And then we set that as the value of the text area with ID address_box.

Conclusion

To force a line break on a JavaScript concatenated string, we add the '\n' string.

Sometimes, we want to change value of input and submit form in JavaScript.

In this article, we’ll look at how to change value of input and submit form in JavaScript.

How to change value of input and submit form in JavaScript?

To change value of input and submit form in JavaScript, we can set the value property of the input.

For instance, we write

<form id="myForm" action="action.php">
  <input type="hidden" name="myInput" value="0" id="myInput" />
  <input type="text" name="message" value="" />
  <input type="submit" name="submit" />
</form>

to add a form.

Then we write

const myForm = document.getElementById("myForm");

myform.onsubmit = () => {
  document.getElementById("myInput").value = "1";
  myForm.submit();
};

to call getElementById to get the form.

Then we set its onsubmit property to a function that’s called when we submit the form.

In it, we get the input with getElementById and set its value to '1'.

And then we call submit to submit the form.

Conclusion

To change value of input and submit form in JavaScript, we can set the value property of the input.

Sometimes, we want to get text area input value with JavaScript.

In this article, we’ll look at how to get text area input value with JavaScript.

How to get text area input value with JavaScript?

To get text area input value with JavaScript, we use the value property.

For instance, we write

<textarea id="textArea"></textarea>

to add the textarea element.

Then we write

document.getElementById("textArea").value = "text";

to select the text area with getElementById.

And then we set its value property to set its input value.

We use the same property to get its input value.

Conclusion

To get text area input value with JavaScript, we use the value property.

Sometimes, we want to download a file from Amazon S3 bucket with JavaScript.

In this article, we’ll look at how to download a file from Amazon S3 bucket with JavaScript.

How to download a file from Amazon S3 bucket with JavaScript?

To download a file from Amazon S3 bucket with JavaScript, we use the AWS Node.js API.

For instance, we write

const AWS = require("aws-sdk");

AWS.config.update({
  accessKeyId: "your key",
  secretAccessKey: "your secret key",
});

const s3 = new AWS.S3();

s3.getObject({ Bucket: "my-bucket", Key: "my-picture.jpg" }, (error, data) => {
  if (error !== null) {
    console.log("Failed to retrieve an object: ", error);
  } else {
    console.log("Loaded " + data.ContentLength + " bytes");
  }
});

to call AWS.config.update to set the keys for accessing S3.

to call getObject with with the bucket and key name to download the file with the given key in the given buckey.

We get the error if there is any.

Conclusion

To download a file from Amazon S3 bucket with JavaScript, we use the AWS Node.js API.

Sometimes, we want to submit two forms with one button with JavaScript.

In this article, we’ll look at how to submit two forms with one button with JavaScript.

How to submit two forms with one button with JavaScript?

To submit two forms with one button with JavaScript, we call submit on each form on click.

For instance, we write

<input type="button" value="Click Me" onclick="submitForms()" />

to add a button.

We set onclick to submitForms() to call submitForms on click.

Then we write

function submitForms() {
  document.getElementById("form1").submit();
  document.getElementById("form2").submit();
}

to get each form with getElementById and call submit on each form.

Conclusion

To submit two forms with one button with JavaScript, we call submit on each form on click.