chooseImageToBase64

export function chooseImage(sourceType = 'album') {
    return new Promise((resolve, reject) => {
        uni.chooseImage({
            count: 1, // 最多可以选择的图片张数，默认9
            sizeType: ['compressed'], // original 原图，compressed 压缩图，默认二者都有
            sourceType: [sourceType], // album 从相册选图，camera 使用相机，默认二者都有
            success: ({ tempFilePaths }) => {
                const tempFilePath = tempFilePaths[0];
                resolve(tempFilePath)
            },
            fail: (err) => {
                console.warn("chooseImage", err);
                reject(err)
            }
        })
    })
}

export function compressImage(src, quality = 80) {
    return new Promise((resolve, reject) => {
        uni.compressImage({
            src: src, // 图片路径，图片的路径，可以是相对路径、临时文件路径、存储文件路径
            quality: quality, // 压缩质量，范围0～100，数值越小，质量越低，压缩率越高（仅对jpg有效）
            success: ({ tempFilePath }) => {
                resolve(tempFilePath);
            },
            fail: (err) => {
                console.warn("compressImage", err);
                reject(err)
            }
        })
    })
}

export function urlToBase64(url, extension = 'png') {
    return new Promise((resolve, reject) => {
        uni.request({
            url: url, 
            method: 'GET',
            responseType: 'arraybuffer',
            success: (res) => {
                let base64 = uni.arrayBufferToBase64(res.data);
                let base64Url = `data:image/${extension};base64,${base64}`;
                resolve(base64Url);
            },
            fail: (err) => {
                console.warn("urlToBase64", err);
                reject(err)
            }
        })
    })
}

/**
 * @param {String} sourceType: album 从相册选图，camera 使用相机，
 * @param {Number} quality 压缩质量，范围0～100，数值越小，质量越低，压缩率越高（仅对jpg有效）
 * @param {String} extension 拓展名 png jpg
 */

export default function chooseImageToBase64(sourceType = 'album', quality = 80, extension = 'png') { // 
    return new Promise((resolve, reject) => {
        chooseImage(sourceType).then(tempFilePath => {
            compressImage(tempFilePath, quality).then(tempFilePath => {
                urlToBase64(tempFilePath, extension).then(base64 => {
                    resolve(base64)
                })
            })
        })
    })
}