Preview an Image on the Client Side
To preview an image before uploading it, you can leverage HTML's file input and the URL.createObjectURL() method. Here's a detailed solution that works entirely within the browser:
In your HTML form, add an input field that allows selecting an image:
<form runat="server"> <input accept="image/*" type='file'>
Next, create an image element to display the preview:
<img>
Finally, add JavaScript that captures the file selected in the input field and uses its content to create an object URL that is then assigned to the image element's src attribute:
imgInp.onchange = evt => {
const [file] = imgInp.files;
if (file) {
blah.src = URL.createObjectURL(file);
}
};
When a user selects an image in the input field, this code will dynamically update the image element, displaying a preview of the selected image without having to upload it to a server. This approach is convenient and efficient for presenting an instant preview of image files on the client side before the user commits to uploading them.
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