[Vuejs]-Object is possibly 'null' despite wrapping problem in if statement

by

3👍

✅

It’s not saying that arr[0] might be null, it’s saying that .match(/:(.*?);/) might return null. So to check for this would be:

const match = arr[0].match(/:(.*?);/);
if (match) {  
  const mime = match[1];
  // ... the rest of the code
}
👤Nicholas Tower

0👍

you can change
from arr[0].match(/:(.*?);/)[1];
to arr[0].match(/:(.*?);/)?[1];

it is coming from second index, not the first one.

👤Sabri Korkmaz

0👍

I could rewrite it this way

dataURLtoBlob(dataurl: string): Blob {
    const arr: string[] = dataurl.split(',');

    // fail fast
    if(!Array.isArray(arr) || !arr[0] || !arr[1])
        return new Blob();
    // can change this to const if you are not planning to set a default mimetype
    let mime = arr[0].match(/:(.*?);/)[1];
    // or you can force typescript compiler to consider this as (string or whatever is the type) with type casting as follow
    // const mime = <string>arr[0].match(/:(.*?);/)[1];
    // const mime = arr[0].match(/:(.*?);/)[1] as string; whatever you like
    if(!mime)
    // mime = 'default mime' in case you have a default mime type
    // or return new Blob() or anything you plan to do in case mime type does not exist

    const bstr = atob(arr[1]);
    let n = bstr.length;
    const u8arr = new Uint8Array(n);

    while (n--) {
        u8arr[n] = bstr.charCodeAt(n);
    }

    return new Blob([u8arr], { type: mime });  
}

This way you don’t end up with deep level nested blocks which usually is hard to read.

👤tbuglc

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