如何将文件转换为Base64格式的data URL在线工具？

粘贴文件或 const input = document.querySelector("#uploadFile"); if (!(input instanceof HTMLInputElement)) throw new TypeError(); const outputWrapper = document.querySelector("#output"); if (!outputWrapper) throw new TypeError(); const fileReader = new FileReader(); /** * @param {FileList} files */ async function handleInput(files) { for (const file of files) { await new Promise(resolve => { fileReader.readAsDataURL(file); fileReader.addEventListener("load", resolve, { once: true }); }); const details = document.createElement("details"); details.innerHTML = `<summary>${file.name}<button>Copy</button></summary><code>${fileReader.result}</code>`; const copyButton = details.querySelector("button"); if (!copyButton) throw new TypeError(); copyButton.addEventListener("click", async () => { await navigator.clipboard.writeText(details.querySelector("code").textContent); copyButton.innerText = "Copied"; }); outputWrapper.appendChild(details); } } input.addEventListener("change", async () => { if (!input.files) throw new TypeError(); handleInput(input.files); }); document.querySelector("#pasteArea").addEventListener("paste", (event) => { if (!(event instanceof ClipboardEvent)) throw new TypeError(); handleInput(event.clipboardData.files); });