32 lines
891 B
TypeScript
32 lines
891 B
TypeScript
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export enum fileReaderType {
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text = "text",
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dataURL = "dataURL",
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}
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/**
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* Read a file using the FileReader API, either as a plain text string or as a DataURL string.
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* Returns a promise which will resolve with the file contents as a string or reject with a DOMException.
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*
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* @param {File} fileHandle - File object to read
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* @param {fileReaderType} type - How to read it
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*/
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export function readFile(fileHandle: File, type: fileReaderType) {
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return new Promise((resolve, reject) => {
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const reader = new FileReader();
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reader.onload = () => resolve(reader.result);
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reader.onerror = () => reject(reader.error);
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switch (type) {
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case fileReaderType.text:
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reader.readAsText(fileHandle);
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break;
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case fileReaderType.dataURL:
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reader.readAsDataURL(fileHandle);
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break;
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default:
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reject("unknown type");
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}
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});
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}
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