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myStorage

myStorage localstorage

このスクリプトは単体で利用できません。右のようなメタデータを含むスクリプトから、ライブラリとして読み込まれます: // @require https://update.greasyfork.org/scripts/390865/738839/myStorage.js

このスクリプトの質問や評価の投稿はこちら通報はこちらへお寄せください。
class myStorage {
    
    constructor(version = 1, prefix = "") {
        this.version = version;
        this.prefix = prefix;
    }
    // Greasemonkey storage API
    read(key, defaultValue) {
        const raw = GM_getValue(this._prefix(key), defaultValue);
        // let str = (this.compress) ? LZString.decompressFromUTF16(raw) : raw;
        return this._parse(raw);
    }
    write(key, value) {
        const raw = this._stringify(value);
        // let str = (this.compress) ? LZString.compressToUTF16(raw) : raw;
        return GM_setValue(this._prefix(key), raw);
    }
    delete(key) {
        return GM_deleteValue(this._prefix(key));
    }

    readKeys() {
        return GM_listValues();
    }
    // browser localstorage
    // read(key, defaultValue) {
    //     const raw = localStorage.getItem(this._prefix(key), defaultValue);
    //     const val = raw || defaultValue;
    //     // const str = (this.compress) ? LZString.decompressFromUTF16(val) : val;
    //     // return this._parse(str);
    //     return this._parse(val);
    // }
    // write(key, value) {
    //     const raw = this._stringify(value);
    //     // let str = (this.compress) ? LZString.compressToUTF16(raw) : raw;
    //     localStorage.setItem(this._prefix(key), raw);
    //     return;
    // }
    // delete(key) {
    //     return localStorage.removeItem(this._prefix(key));
    // }
    // readKeys() {
    //     let keys = [];
    //     for(let i=0, l=localStorage.length; i < l; i++){
    //        keys.push( localStorage.getItem(localStorage.key(i)) );
    //     }
    //     return keys;
    // }

    // “Set” means “add if absent, replace if present.”
    set(key, value) {
        let savedVal = this.read(key);

        if (typeof savedVal === 'undefined' || !savedVal) {
            // add if absent
            return this.add(key, value);
        } else {
            // replace if present
            this.write(key, value);
            return true;
        }
    }

    // “Add” means “add if absent, do nothing if present” (if a uniquing collection).
    add(key, value) {
        let savedVal = this.read(key, false);

        if (typeof savedVal === 'undefined' || !savedVal) {
            this.write(key, value);
            return true;
        } else {
            if (this._isArray(savedVal)) { // is array
                let index = savedVal.indexOf(value);

                if (index !== -1) {
                    // do nothing if present
                    return false;
                } else {
                    // add if absent
                    savedVal.push(value);
                    this.write(key, savedVal);
                    return true;
                }
            } else if (this._isObject(savedVal)) { // is object
                // merge obj value on obj
                let result, objToMerge = value;

                result = Object.assign(savedVal, objToMerge);
                this.write(key, result);
                return false;
            }
            return false;
        }
    }

    // “Replace” means “replace if present, do nothing if absent.”
    replace(key, itemFind, itemReplacement) {
        let savedVal = this.read(key, false);

        if (typeof savedVal === 'undefined' || !savedVal) {
            // do nothing if absent
            return false;
        } else {
            if (this._isArray(savedVal)) { // is Array
                let index = savedVal.indexOf(itemFind);

                if (index !== -1) {
                    // replace if present
                    savedVal[index] = itemReplacement;
                    this.write(key, savedVal);
                    return true;
                } else {
                    // do nothing if absent
                    return false;
                }
            } else if (this._isObject(savedVal)) {
                // is Object
                // replace property's value
                savedVal[itemFind] = itemReplacement;
                this.write(key, savedVal);
                return true;
            }
            return false;
        }
    }

    // “Remove” means “remove if present, do nothing if absent.”
    remove(key, value) {
        if (typeof value === 'undefined') { // remove key
            this.delete(key);
            return true;
        } else { // value present
            let savedVal = this.read(key);

            if (typeof savedVal === 'undefined' || !savedVal) {
                return true;
            } else {
                if (this._isArray(savedVal)) { // is Array
                    let index = savedVal.indexOf(value);

                    if (index !== -1) {
                        // remove if present
                        savedVal.splice(index, 1);
                        this.write(key, savedVal);
                        return true;
                    } else {
                        // do nothing if absent
                        return false;
                    }
                } else if (this._isObject(savedVal)) { // is Object
                    let property = value;

                    delete savedVal[property];
                    this.write(key, savedVal);
                    return true;
                }
                return false;
            }
        }
    }

    get(key, defaultValue) {
        return this.read(key, defaultValue);
    }

    getAll() {
        const keys = this._listKeys();
        let obj = {};

        for (let i = 0, len = keys.length; i < len; i++) {
            obj[keys[i]] = this.read(keys[i]);
        }
        return obj;
    }

    getKeys() {
        return this._listKeys();
    }

    getPrefix() {
        return this.prefix;
    }

    empty() {
        const keys = this._listKeys();

        for (let i = 0, len = keys.lenght; i < len; i++) {
            this.delete(keys[i]);
        }
    }

    has(key) {
        return this.get(key) !== null;
    }

    forEach(callbackFunc) {
        const allContent = this.getAll();

        for (let prop in allContent) {
            callbackFunc(prop, allContent[prop]);
        }
    }

    _parse(value) {
        if (this._isJson(value)) {
            return JSON.parse(value);
        }
        return value;
    }

    _stringify(value) {
        if (this._isJson(value)) {
            return value;
        }
        return JSON.stringify(value);
    }

    _listKeys(usePrefix = false) {
        const prefixed = this.readKeys();
        let unprefixed = [];

        if (usePrefix) {
            return prefixed;
        } else {
            for (let i = 0, len = prefixed.length; i < len; i++) {
                unprefixed[i] = this._unprefix(prefixed[i]);
            }
            return unprefixed;
        }
    }

    _prefix(key) {
        return this.prefix + key;
    }

    _unprefix(key) {
        return key.substring(this.prefix.length);
    }

    _isJson(item) {
        try {
            JSON.parse(item);
        } catch (e) {
            return false;
        }
        return true;
    }

    _isObject(a) {
        return (!!a) && (a.constructor === Object);
    }

    _isArray(a) {
        return (!!a) && (a.constructor === Array);
    }
}