function selectImagesToUpload() {
const input = document.getElementById("product_pics");
const preview = document.querySelector(".preview");
const images = preview.querySelectorAll("div.preview > p");
images.forEach(async item => {
let fn = item.innerText.split(';')[0];
let ext = fn.slice(fn.lastIndexOf('.') + 1, fn.length);
let p = await fetch(fn).then(response => response.blob());
let b = await p.arrayBuffer();
let f0 = new File(new Uint8Array(b), fn, { type: `image/${ext}` });
var reader = new FileReader();
reader.onload = function (e) {
var image = document.createElement("img");
image.src = e.target.result;
document.body.appendChild(image);
}
reader.readAsDataURL(f0);
});
}这是一个相对URL的示例段落（我将其设置在项目的资产中）：
img/prodotto7.jpg;< p > < /p >这是附加到DOM的结果：
emptyimage有人可以帮我吗？这就像一个测试一样，我必须努力继续我的项目。
对一些疯狂的技巧进行评估，我得到了“无效的chalidcharactererror：未能在'窗口'上执行'atob'：要解码的字符串未正确编码。”在“ ATOB（e.target.result）”的行中；因此，fileReader做得不正确。
let fn = item.innerText.split(';')[0];
let ext = fn.slice(fn.lastIndexOf('.') + 1, fn.length);
let p = await fetch(fn).then(response => response.blob());
let b = await p.arrayBuffer();
let ua = new Uint8Array(b)
let u64 = ua.toBase64;
let f0 = new File( ua , fn, { type: `image/${ext}` });
console.log(f0);
const para = document.createElement("p");
para.textContent = item.textContent;
preview.appendChild(para);
var reader = new FileReader()
reader.onload = function (e) {
var image = document.createElement("img");
image.src = e.target.result;
console.log(image.src);
var bs = atob(e.target.result);
var buffer = new ArrayBuffer(bs.length);
var ba = new Uint8Array(buffer);
for (var i = 0; i < bs.length; i++) {
ba[i] = bs.charCodeAt(i);
}
var blob = new Blob([ba], { type: "image/jpg" });
document.body.appendChild(URL.createObjectURL(blob));
}
reader.readAsDataURL(f0);
溶解（我需要文件变量的机制 - 转换图像，然后将它们恢复 - 将图像存储到filelist中，然后在formdata变量中存储，并在最终的范围内发布并通过微服务器获得消息，任务完整！）
.ts部分
...
formData !: FormData;
fileTypes = [
"image/apng",
"image/bmp",
"image/gif",
"image/jpeg",
"image/pjpeg",
"image/png",
"image/svg+xml",
"image/tiff",
"image/webp",
"image/x-icon",
];
...
selectImagesToUpload($event : any) {
const fl = new Promise<File[]>( (resolve, reject) => {
console.log('promise');
const input = document.getElementById("product_pics");
const preview = document.querySelector(".preview");
const images = preview?.querySelectorAll("div.preview > p");
let fl: File[] = new Array();
console.log(fl);
images?.forEach(async item => {
if (preview?.firstChild === undefined) {
/* *** TODO ***
console.log('primo');
const para = document.createElement("p");
console.log(item.innerText);
para.textContent = item.textContent;
preview.appendChild(para);
fl[i] = */
} else {
console.log('secondo');
console.log(item.textContent);
let fn = item?.textContent?.split(';')[0];
let ext = fn?.slice(fn.lastIndexOf('.') + 1, fn.length);
if (fn) {
let p = await fetch(fn).then(response => response.blob());
let b = await p.arrayBuffer();
let ua = new Uint8Array(b)
//console.log(ua)
//let b64 = ua.toBase64(); //it does not work in some of the most widely-used browsers.
const bin = [];
for (let i = 0; i < ua.length; i++) {
bin.push(String.fromCharCode(ua[i]));
}
const b64encoded = btoa(bin.join(""));
//console.log(b64encoded);
const trimmedString = b64encoded.replace('dataimage/jpegbase64', '');
const imageContent = atob(trimmedString);
const buffer = new ArrayBuffer(imageContent.length);
const view = new Uint8Array(buffer);
for (let n = 0; n < imageContent.length; n++) {
view[n] = imageContent.charCodeAt(n);
}
const type = `image/${ext}`;
const blob = new Blob([buffer], { type });
let f0 = new File([blob], fn, { lastModified: new Date().getTime(), type });
var image = document.createElement("img");
image.src = `data:image/png;base64, ${b64encoded}`;
//console.log(image.src)
console.log(f0);
document.body.appendChild(image); //image shown
this.Main(f0); //file shown
const para = document.createElement("p");
console.log(`filename : ${fn};`);
para.textContent = `${fn};`;
preview.appendChild(para);
fl.push(f0);
}
}
});
while (preview?.firstChild) {
preview.removeChild(preview.firstChild);
}
const curFiles = (<HTMLInputElement>input)?.files;
if (curFiles?.length === 0) {
} else {
if (curFiles) {
for (const file of curFiles) {
if (this.validFileType(file)) {
let filename = String(file.name);
let image = filename.slice(0, filename.lastIndexOf('.'));
if (this.validImage(image)) {
const para = document.createElement("p");
console.log(`filename : ${file.name};`);
para.textContent = `${filename};`;
preview?.appendChild(para);
fl.push(file);
this.Main(file); //file shown
}
}
}
}
}
resolve(fl);
});
fl.then(
(fl) => {
let fd = new FormData();
console.log('1then');
console.log(fl);
for (let i = 0; i < fl.length; i++) {
fd.append(fl[i].name, fl[i]);
}
this.formData = fd;
},
(err) => {
console.log('errore');
console.log(err);
}).then(
resolve => {
console.log('2then');
for (const pair of this.formData.entries()) {
console.log(pair[0], pair[1]);
}
});
}
clearValues($event: any) {
this.clearAllImages();
}
validFileType(file: File) {
return this.fileTypes.includes(file.type);
}
validImage(image: string) {
return !image.includes(';') && !image.includes('.');
}
clearAllImages() {
const preview = document.querySelector(".preview");
const images = preview?.querySelector("div.preview > p");
while (preview?.firstChild) {
preview.removeChild(preview.firstChild);
}
}
async Main(file: any) {
const toBase64 = (file: any) => new Promise((resolve, reject) => {
const reader = new FileReader();
reader.readAsDataURL(file);
reader.onload = () => {
resolve(reader.result);
}
reader.onerror = reject;
});
let b64 = await toBase64(file);
//console.log(b64);
var image = document.createElement("img");
image.src = String(b64);
//let u8 = Uint8Array.fromBase64(b64); //it does not work in some of the most widely-used browsers.
document.body.appendChild(image);
}
HTML部分
<section class="content-main main d-flex flex-column justify-content-center">
<div class="content-header d-flex flex-column">
<h2 class="content-title d-flex justify-content-center">{{title}}</h2>
<div>
<button class="btn btn-outline-danger" (click)="abort()"> × Annulla></button>
</div>
</div>
<div class="scheda d-flex align-items-center justify-content-around">
<div class="card">
<form (ngSubmit)="artForm.valid && Salva()" #artForm="ngForm" enctype="multipart/form-data">
<!-- Codice, Barcode -->
<div class="row gx-2">
<div class="col-sm-6 mb-3">
<label for="codArt" class="form-label">Codice Articolo:</label>
<input id="codArt" name="codart" type="text" placeholder="" class="form-control" [(ngModel)]="articolo.codprod"
required minlength="5" maxlength="30" #codice="ngModel">
<span style="color:red" *ngIf="codice.invalid && (codice.dirty || codice.touched)">
Il codice articolo deve essere compreso fra 5 e 30 caratteri
</span>
</div>
</div>
<!--Descrizione -->
<div class="mb-4">
<label class="form-label">Descrizione Articolo</label>
<textarea placeholder="" name="descr" class="form-control" rows="2" [(ngModel)]="articolo.descrizione"
required minlength="6" maxlength="80" #desart="ngModel"></textarea>
<span style="color:red" *ngIf="desart.invalid && (desart.dirty || desart.touched)">
Il codice articolo deve essere compreso fra 6 e 80 caratteri
</span>
</div>
<!--Unità di misura, Iva -->
<div class="row gx-2">
<div class="col-sm-6 mb-3">
<label class="form-label">Unità di Misura</label>
<select class="form-select" name="um" [(ngModel)]="articolo.um">
<option value="pz"> Pezzi </option>
<option value="kg"> Kilogrammi </option>
</select>
</div>
<div class="col-sm-6 mb-3">
<label class="form-label">Iva</label>
<select class="form-select" name="iva" [(ngModel)]="articolo.iva.idIva">
<option value="-1" class="text-primary font-weight-bolder">--- Seleziona IVA ---</option>
<option [ngValue]="iva.idIva" *ngFor="let iva of Iva">
{{iva.descrizione}}
</option>
</select>
</div>
</div> <!-- row.// -->
<!-- Pezzi per cartone, Peso, Prezzo, Valuta -->
<div class="mb-4">
<label class="form-label">Pezzi Per Cartone: Peso Netto:</label>
<div class="row gx-2">
<div class="col-3">
<input placeholder="Pezzi" type="text" class="form-control" [(ngModel)]="articolo.pz"
required min="1" name="pzcart" max="99" maxlength="3" #pzcart="ngModel">
<span style="color:red" *ngIf="pzcart.errors?.['required']">
Inserisci i pezzi per cartone
</span>
<span style="color:red" *ngIf="pzcart.errors?.['min']">
Il valore minimo è 1
</span>
<span style="color:red" *ngIf="pzcart.errors?.['max']">
Il valore massimo è 99
</span>
</div>
<div class="col-3">
<input placeholder="Peso" name="peso" type="text" class="form-control" [(ngModel)]="articolo.peso"
required maxlength="6" min="0.01" max="500" #peso="ngModel">
<span style="color:red" *ngIf="peso.invalid && (peso.dirty || peso.touched)">
Il peso dell'articolo deve essere compreso tra 0.01 e 500
</span>
</div>
<div class="col-4">
<input placeholder="Prezzo" type="text" class="form-control">
</div>
<div class="col-2">
<select class="form-select">
<option> EUR </option>
<option> USD </option>
<option> GBP </option>
</select>
</div>
</div>
</div>
<!-- Categoria, Stato Articolo -->
<div class="row gx-2">
<div class="col-sm-6 mb-3">
<label class="form-label">Categoria:</label>
<select class="form-select" name="cat" [(ngModel)]="articolo.famAssort.id">
<option [ngValue]="categoria.id" *ngFor="let categoria of Cat">
{{categoria.id}} - {{categoria.descrizione}}
</option>
</select>
</div>
<div class="col-sm-6 mb-3">
<label class="form-label">Stato:</label>
<select class="form-select" name="status" [(ngModel)]="articolo.status">
<option value="1">Attivo</option>
<option value="2">Sospeso</option>
<option value="3">Eliminato</option>
</select>
</div>
</div> <!-- row.// -->
<!-- Immagine -->
<div class="mb-4">
<label class="form-label">Immagine:</label>
<input class="form-control" type="file"
enctype="multipart/form-data"
id="product_pics"
name="product_pics"
accept=".jpg, .jpeg, .png"
(change)="selectImagesToUpload($event)" multiple />
<!application/x-www-form-urlencoded-->
<button class="btn btn-primary" (click)="clearValues($event)">Clear all</button>
</div>
<div id="uploadImages" class="preview">
@if(articolo.imgsrc){
<p>{{articolo.imgsrc}};</p>
}@else{
<p>No files currently selected for upload</p>
}
</div>
<div class="alert alert-success" *ngIf="Conferma">
{{Conferma}}
</div>
<div class="alert alert-danger" *ngIf="errore">
{{errore}}
</div>
<br>
<button type="submit" class="btn btn-primary" [disabled]="artForm.invalid">Salva Articolo</button>
</form>
</div>
</div>