javascript function returns as “null” instead of null value
I have this javascript function:
getToken: function ()
return localStorage.jwtToken;
,
this.getToken()!=null //true,
so basically this function returns "null" instead of null, how can I make the function return the null value?
javascript
asked Nov 13 '18 at 21:24
user3306308user3306308
305
add a comment |
I have this javascript function:
getToken: function ()
return localStorage.jwtToken;
,
this.getToken()!=null //true,
so basically this function returns "null" instead of null, how can I make the function return the null value?
javascript
asked Nov 13 '18 at 21:24
user3306308user3306308
305
1
Possible duplicate of Storing Objects in HTML5 localStorage
– lucascaro
Nov 13 '18 at 21:27
1
How did you set the value? You've confirmed thatthis.getToken()returns"null"?
– Tyler Roper
Nov 13 '18 at 21:31
add a comment |
I have this javascript function:
getToken: function ()
return localStorage.jwtToken;
,
this.getToken()!=null //true,
so basically this function returns "null" instead of null, how can I make the function return the null value?
javascript
asked Nov 13 '18 at 21:24
user3306308user3306308
305
I have this javascript function:
getToken: function ()
return localStorage.jwtToken;
,
this.getToken()!=null //true,
so basically this function returns "null" instead of null, how can I make the function return the null value?
javascript
javascript
asked Nov 13 '18 at 21:24
user3306308user3306308
305
asked Nov 13 '18 at 21:24
user3306308user3306308
305
asked Nov 13 '18 at 21:24
user3306308user3306308
305
asked Nov 13 '18 at 21:24
user3306308user3306308
305
asked Nov 13 '18 at 21:24
user3306308user3306308
305
305
1
Possible duplicate of Storing Objects in HTML5 localStorage
– lucascaro
Nov 13 '18 at 21:27
1
How did you set the value? You've confirmed thatthis.getToken()returns"null"?
– Tyler Roper
Nov 13 '18 at 21:31
add a comment |
1
Possible duplicate of Storing Objects in HTML5 localStorage
– lucascaro
Nov 13 '18 at 21:27
1
How did you set the value? You've confirmed thatthis.getToken()returns"null"?
– Tyler Roper
Nov 13 '18 at 21:31
1
1
Possible duplicate of Storing Objects in HTML5 localStorage
– lucascaro
Nov 13 '18 at 21:27
Possible duplicate of Storing Objects in HTML5 localStorage
– lucascaro
Nov 13 '18 at 21:27
1
1
How did you set the value? You've confirmed that
this.getToken() returns "null"?– Tyler Roper
Nov 13 '18 at 21:31
How did you set the value? You've confirmed that
this.getToken() returns "null"?– Tyler Roper
Nov 13 '18 at 21:31
add a comment |
3 Answers
3
active
oldest
votes
You probably did:
localStorage.jwtToken = null;
to set it to null, but as localStorage can only contain string properties, it got stringified to "null". Instead of setting it to null set it to undefined, or just delete the key:
localStorage.jwtToken = undefined;
localStorage.removeItem("jwtToken");
answered Nov 13 '18 at 21:27
Jonas WilmsJonas Wilms
59.1k53152
add a comment |
If instead of "null" you want to return null, return this expression
getToken: function ()
let token = localStorage.jwtToken;
return (token === "null") ? null : token;
answered Nov 13 '18 at 21:46
Sergey PleshakovSergey Pleshakov
210113
add a comment |
this.getToken()!=null returns true because you are only checking the value.
If you want to check the value and type you need to check with !==.
this.getToken() !== null
answered Nov 13 '18 at 21:27
Pablo DardePablo Darde
1,50311527
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
You probably did:
localStorage.jwtToken = null;
to set it to null, but as localStorage can only contain string properties, it got stringified to "null". Instead of setting it to null set it to undefined, or just delete the key:
localStorage.jwtToken = undefined;
localStorage.removeItem("jwtToken");
answered Nov 13 '18 at 21:27
Jonas WilmsJonas Wilms
59.1k53152
add a comment |
You probably did:
localStorage.jwtToken = null;
to set it to null, but as localStorage can only contain string properties, it got stringified to "null". Instead of setting it to null set it to undefined, or just delete the key:
localStorage.jwtToken = undefined;
localStorage.removeItem("jwtToken");
answered Nov 13 '18 at 21:27
Jonas WilmsJonas Wilms
59.1k53152
add a comment |
You probably did:
localStorage.jwtToken = null;
to set it to null, but as localStorage can only contain string properties, it got stringified to "null". Instead of setting it to null set it to undefined, or just delete the key:
localStorage.jwtToken = undefined;
localStorage.removeItem("jwtToken");
answered Nov 13 '18 at 21:27
Jonas WilmsJonas Wilms
59.1k53152
You probably did:
localStorage.jwtToken = null;
to set it to null, but as localStorage can only contain string properties, it got stringified to "null". Instead of setting it to null set it to undefined, or just delete the key:
localStorage.jwtToken = undefined;
localStorage.removeItem("jwtToken");
answered Nov 13 '18 at 21:27
Jonas WilmsJonas Wilms
59.1k53152
edited Nov 13 '18 at 21:38
answered Nov 13 '18 at 21:27
Jonas WilmsJonas Wilms
59.1k53152
answered Nov 13 '18 at 21:27
Jonas WilmsJonas Wilms
59.1k53152
answered Nov 13 '18 at 21:27
Jonas WilmsJonas Wilms
59.1k53152
59.1k53152
add a comment |
add a comment |
If instead of "null" you want to return null, return this expression
getToken: function ()
let token = localStorage.jwtToken;
return (token === "null") ? null : token;
answered Nov 13 '18 at 21:46
Sergey PleshakovSergey Pleshakov
210113
add a comment |
If instead of "null" you want to return null, return this expression
getToken: function ()
let token = localStorage.jwtToken;
return (token === "null") ? null : token;
answered Nov 13 '18 at 21:46
Sergey PleshakovSergey Pleshakov
210113
add a comment |
If instead of "null" you want to return null, return this expression
getToken: function ()
let token = localStorage.jwtToken;
return (token === "null") ? null : token;
answered Nov 13 '18 at 21:46
Sergey PleshakovSergey Pleshakov
210113
If instead of "null" you want to return null, return this expression
getToken: function ()
let token = localStorage.jwtToken;
return (token === "null") ? null : token;
answered Nov 13 '18 at 21:46
Sergey PleshakovSergey Pleshakov
210113
answered Nov 13 '18 at 21:46
Sergey PleshakovSergey Pleshakov
210113
answered Nov 13 '18 at 21:46
Sergey PleshakovSergey Pleshakov
210113
answered Nov 13 '18 at 21:46
Sergey PleshakovSergey Pleshakov
210113
210113
add a comment |
add a comment |
this.getToken()!=null returns true because you are only checking the value.
If you want to check the value and type you need to check with !==.
this.getToken() !== null
answered Nov 13 '18 at 21:27
Pablo DardePablo Darde
1,50311527
add a comment |
this.getToken()!=null returns true because you are only checking the value.
If you want to check the value and type you need to check with !==.
this.getToken() !== null
answered Nov 13 '18 at 21:27
Pablo DardePablo Darde
1,50311527
add a comment |
this.getToken()!=null returns true because you are only checking the value.
If you want to check the value and type you need to check with !==.
this.getToken() !== null
answered Nov 13 '18 at 21:27
Pablo DardePablo Darde
1,50311527
this.getToken()!=null returns true because you are only checking the value.
If you want to check the value and type you need to check with !==.
this.getToken() !== null
answered Nov 13 '18 at 21:27
Pablo DardePablo Darde
1,50311527
answered Nov 13 '18 at 21:27
Pablo DardePablo Darde
1,50311527
answered Nov 13 '18 at 21:27
Pablo DardePablo Darde
1,50311527
answered Nov 13 '18 at 21:27
Pablo DardePablo Darde
1,50311527
1,50311527
add a comment |
add a comment |
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1
Possible duplicate of Storing Objects in HTML5 localStorage
– lucascaro
Nov 13 '18 at 21:27
1
How did you set the value? You've confirmed that
this.getToken()returns"null"?– Tyler Roper
Nov 13 '18 at 21:31