我的回复包含一个 png，我如何在反应中显示图像，因为它不是 url？

Question

I have a response containing an image in png format,but I am unable to display it in react since it is not a url pic of response

does anyone know how I can convert this png into a URL so I can insert it into my src of img tag?

Answer 1

If you have the image inside your application ( assets folder or whatever ) you could display it like that

<img src={`assets/${coverImage}`}>

Else The image should be sent from the API in the base64 format and then you could simply display it like that.

data = "base64 image"
<img src={`data:image/jpeg;base64,${data}`} />

Answer 2

Why not treat imege you need as Bese64 string?
If you're able to convert you png image to a Base64 string (server side obviously) you can easily use it in img tag as src attribute value.

Answer 3

This is something I did when I was doing a similar thing in a React project.

1) Assuming the following:

• The response that we get from the API is not BASE64 encoded
• The responseType is not specified in the request
• A png is the response

The response data will look like this:

With characters that does not look friendly.

2) With changed responseType

• Set responseType: "arraybuffer" in the request

The response will now have arrayBuffer in data of the response

The response can then be converted to base64 by

let base64ImageString = Buffer.from(response.data, 'binary').toString('base64')

If you want to display it on an img tag, then prepend data:image/png;base64, to the Base64 string

let srcValue = "data:image/png;base64,"+base64ImageString

But in your case, it seems like you are only getting the file name as a string and not the file itself.

Answer 4

same in my case. "react": "17.0.1", "react-native": "0.64.2",
my response contains png image(no URL, no base64), I converted my response into base64 as below,

const makeApiRequest = async()=>{
    try {
        const response = await apiCaller('ProfileImage',{"thisID": "ABCD","thatID": "1234"})
        if(response.status === 200){
            const dataResponse = await response.blob()
            let blob = new Blob([dataResponse], { type: "text/plain" });
            var reader = new FileReader();
            reader.readAsDataURL(blob);
            reader.onloadend = function () {
               var base64String = reader.result; 
               setImageFromAPI(base64String.substr(base64String.indexOf(', ') + 1)); //Setting response to hook
            }
        }else{
            console.log(response.status)
        }
    } catch (error) {
        console.log("components/profile/ProfileTimeline.js:-",error)
    }
}

But when I use it in my image tag its shows no image, and i don't know why

<Image  source={{uri: `data:image/png;base64,${imagefromAPI}`}}  style={{width:100, height:100}} resizeMode="cover" />