I have another line of code as shown blow, which will give users Save As option. Next we have render function to render the elements of React app. Elements are the building blocks of React apps. As we said in Introduction section that we will give users two options for downloading file using link or using button.
So in this render function we define our HTML elements with button and link to download file. Export the DownloadFile at the end of the DownloadFile class so that you can use this class in other modules, such as, I have used it later in below index. Notice I had included download. This file is put under the src directory. The download. Update the index. To import a class you must first have to export it as we did for DownloadFile in the last line.
When you click any one of the download options — link or button, then you will see below output on the browser. You can choose any location to save your file. You may also like to read How to download file from server using Angular. But before you tackle the big projects, we suggest you start by learning the basics. Now at it's lowest price ever! Approach 2: Using a custom javascript function firstly made a textarea where all the text input will be issued.
The click method simulates a mouse-click on an element. This requires a little intermediate knowledge of the JavaScript to work and in this example a Axios library will be used.
Skip to content. Change Language. Related Articles. Table of Contents. Improve Article. Save Article. That sounds like a good opportunity to use a FileReader object. You can learn about FileReader objects here.
A FileReader object provides some very helpful methods for asynchronously reading the content of blob objects or files in different ways. The FileReader interface has pretty good browser support and supports reading blob data as follows as at the time of this writing :. Here is what a typical object URL looks like:. The URL. Here is what it looks like:. It is important to note that, this method will always return a new object URL each time it is called, even if it is called with the same blob object.
Whenever an object URL is created, it stays around for the lifetime of the document on which it was created. Usually, the browser will release all object URLs when the document is being unloaded.
However, it is important that you release object URLs whenever they are no longer needed in order to improve performance and minimize memory usage. It takes the object URL to be released as its argument. For example:. We have also seen how we can programmatically extract or generate content in the browser using Web APIs. In this section, we will examine how we can download programmatically generate content in the browser, leveraging all we have learned from the beginning of the article and what we already know about blobs and object URLs.
The logic of our helper function can be broken down as follows:. Here is what an implementation of this helper function will look like:. That was a pretty straightforward implementation of the download link helper function. Notice that the helper triggers a one-off automatic download of the blob content whenever it is called. Also notice that the helper function takes a filename as its second argument, which is very useful for setting the default filename for the downloaded file.
Now that we have our download helper function in place, we can revisit our previous examples and modify them to trigger a download for the generated content. Here we go. We will update the final promise. Here we have updated the final promise. Here is a working and more advanced example of this application on Codepen :.
We will add some code to the end of the load event listener of the img object, to allow us:. Here is a working example of this application on Codepen :. While there could be a lot to pick from this tutorial, it is glaring that Web APIs have a lot to offer as regards building powerful apps for the browser. Thanks for making out time to read this article.
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