/**
|
* @description: base64 to blob
|
*/
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export function dataURLtoBlob(base64Buf: string): Blob {
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const arr = base64Buf.split(',');
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const typeItem = arr[0];
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const mime = typeItem.match(/:(.*?);/)![1];
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const bstr = window.atob(arr[1]);
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let n = bstr.length;
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const u8arr = new Uint8Array(n);
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while (n--) {
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u8arr[n] = bstr.charCodeAt(n);
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}
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return new Blob([u8arr], { type: mime });
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}
|
|
/**
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* img url to base64
|
* @param url
|
*/
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export function urlToBase64(url: string, mineType?: string): Promise<string> {
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return new Promise((resolve, reject) => {
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let canvas = document.createElement('CANVAS') as Nullable<HTMLCanvasElement>;
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const ctx = canvas!.getContext('2d');
|
|
const img = new Image();
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img.crossOrigin = '';
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img.onload = function () {
|
if (!canvas || !ctx) {
|
return reject();
|
}
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canvas.height = img.height;
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canvas.width = img.width;
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ctx.drawImage(img, 0, 0);
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const dataURL = canvas.toDataURL(mineType || 'image/png');
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canvas = null;
|
resolve(dataURL);
|
};
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img.src = url;
|
});
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}
|
|
/**
|
* File转Base64
|
* @param file
|
*/
|
export function fileToBase64(file: Blob) {
|
return new Promise((resolve, reject) => {
|
const reader = new FileReader();
|
reader.readAsDataURL(file);
|
reader.onload = () => resolve(reader.result);
|
reader.onerror = (error) => reject(error);
|
});
|
}
|
|
/**
|
* Base64转File
|
* @param dataURL {String} base64
|
* @param fileName {String} 文件名
|
* @param mimeType {String} [可选]文件类型，默认为base64中的类型
|
* @returns {File}
|
*/
|
export function base64ToFile(dataURL: string, fileName: string, mimeType = null) {
|
var arr = dataURL.split(',');
|
var defaultMimeType = arr[0].match(/:(.*?);/)[1];
|
var bStr = atob(arr[1]);
|
let n = bStr.length;
|
var u8arr = new Uint8Array(n);
|
while (n--) {
|
u8arr[n] = bStr.charCodeAt(n);
|
}
|
return new File([u8arr], fileName, { type: mimeType || defaultMimeType });
|
}
|
|
/**
|
* Blob转File
|
* @param blob {Blob} blob
|
* @param fileName {String} 文件名
|
* @param mimeType {String} 文件类型
|
* @return {File}
|
*/
|
export function blobToFile(blob: Blob, fileName: string, mimeType?: string) {
|
if (mimeType == null) mimeType = blob.type;
|
return new File([blob], fileName, { type: mimeType });
|
}
|
