10 examples of 'check if localstorage exists' in JavaScript

54
export function localStorageExists() {
55
    return lsExists;
56
}

257
function checkForLocalStorage() {
258
    try {
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        localStorage.setItem('test', 'test');
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        localStorage.removeItem('test');
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        return true;
262
    } catch (e) {
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        return false;
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    }
265
}

35
function isLocalStorageAvailable() {
36
    try {
37
        return 'localStorage' in window && window['localStorage'] !== null;
38
    } catch (e) {
39
        console.log("localStorage_failed:", e);
40
        return false;
41
    }
42
};

331
checkIsLocalStorageSupported_() {
332
  try {
333
    if (!('localStorage' in this.win)) {
334
      return false;
335
    }
336
337
    // We do not care about the value fetched from local storage; we only care
338
    // whether the call throws an exception or not.  As such, we can look up
339
    // any arbitrary key.
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    this.win.localStorage.getItem('test');
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    return true;
342
  } catch (e) {
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    return false;
344
  }
345
}

18
function exists (filename, callback) {
19
  localforage.getItem(filename, function (err, value) {
20
    if (value !== null) {   // Even if value is undefined, localforage returns null
21
      return callback(true);
22
    } else {
23
      return callback(false);
24
    }
25
  });
26
}

115
export function localStorageAvailable() {
116
  try {
117
    const storage = window.localStorage;
118
    const x = '__storage_test__';
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    storage.setItem(x, x);
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    storage.removeItem(x);
121
    return true;
122
  } catch (e) {
123
    return false;
124
  }
125
}

44
exists(key) {
45
  return this.get(this.getKey(key)) || false;
46
}

44
exists() {
45
  return fse.pathExists(this.registryFile);
46
}

38
has(key: string) {
39
    try {
40
        return localStorage.getItem(key) != null;
41
    } catch (err) {
42
        console.error(err);
43
        return false;
44
    }
45
}

84
public static isAvailable(): boolean {
85
  return typeof global.localStorage !== 'undefined';
86
}