Angular cli comes with wide range of commands that help manage the angular development, testing and build process. This command creates a new folder named hello-angular and creates all the files and setups the necessary libraries within this folder and makes the angular project ready to be executed without any additional configuration.
Once project is created change into project directory and run application using ng serve command as shown below. As discussed, angular cli comes with great tooling, one of the productive features is webpack hot reloading, which deploys the change on live and saves developer lot of time to redeploy and reload work. We will go through the project structure to understand the importance of the files and folders created.
Open the project which was created in previous step in any JS editor, here you see the project is open in vscode editor. On to the left in explorer section you see file explorer which shows you several folders and files which were created by ng new command. Show 2 more comments. Nikhil Baby Nikhil Baby 3 3 gold badges 8 8 silver badges 21 21 bronze badges. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password.
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Reducing the weight of our footer. Instead let's introduce a data structure representing a download with progress:. A Download can be in one of three states. Either it hasn't started yet, therefore it's pending.
Otherwise it's done or still in progress. We use TypeScript's union types to define the different download states. Additionally, a download has a number indicating the download progress from 1 to Once a download is done, it will contain a Blob as its content - until then this property is not available, therefore null.
Now we want to abstract from specific HTTP events to our newly defined data structure. This way our components can be decoupled from the underlying network protocol. Since we're dealing with multiple events coming in over time, a RxJS operator is well suited here - so let's create one! The first step for this will be the creation of type guards helping us to distinguish different HTTP events. This way we can access event-specific fields in a type-safe way. They both contain the discriminator field type allowing us to easily return a boolean for the type assertion in our guards.
The guards can be used with a simple if-statement, however, TypeScript will narrow the event type inside the statement block for us:. Based on these guards we can now create our custom operator. It'll leverage scan , an operator that allows us to accumulate state for successive values coming through an observable. It takes up to two arguments: First, we provide an accumulator function which will compute the next Download state from the previous one and the current HttpEvent.
Second, we'll pass a seed to scan representing the initial Download state. This seed will represent our download being pending without any progress or content:.
Our accumulator will use the previously defined guard to update the Download state over time with information from the HTTP events:. I will use link as well as button for downloading the same file from the server. In the service class I have used Http module which may not be found automatically. So I need to register it in providers array of NgModule.
Run the Angular application angular-file-download by executing command ng serve --open. When you click on link or button for downloading file you will see below page with file save option:. When you use the code for displaying data on browser inside download function of controller code and click on button or link, then you should see below output:. For server side code you can read the post on Download file using Angular and Spring Boot.
Hi, There is no such step other than running the command for installing file-saver package. You can check what goes wrong in the browser conaole. If only more tutorials on Angular were as succinctly and thoughtfully written as this.
Well done!! I need to show save dialog box to user so he can save file any where.
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