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CSSStyleDeclaration JS Conversion


JavaScript parseInt()

Esempio

Analizza valori diversi:

parseInt("10");
parseInt("10.00");
parseInt("10.33");
parseInt("34 45 66");
parseInt(" 60 ");
parseInt("40 years");
parseInt("He was 40");

Definizione e utilizzo

Il parseIntmetodo analizza un valore come una stringa e restituisce il primo intero.

Un parametro radix specifica il sistema numerico da utilizzare:

2 = binario, 8 = ottale, 10 = decimale, 16 = esadecimale.

Se radix viene omesso, JavaScript presuppone radix 10. Se il valore inizia con "0x", JavaScript assume radix 16.

Appunti

Se il primo carattere non può essere convertito, NaNviene restituito.

Gli spazi iniziali e finali vengono ignorati.

Viene restituito solo il primo numero intero trovato.

I browser meno recenti restituiranno 8 per parseInt("010"). Le versioni precedenti di ECMAScript utilizzavano ottale (radice 8) per i valori che iniziano con "0". Da ECMAScript 5 (2009) l'impostazione predefinita è decimale (radice 10).


Sintassi

parseInt(string, radix)

Parametri

Parameter Description
value Required.
The value to be parsed.
radix Optional. Default is 10.
A number (2 to 36) specifying the number system.

Valore di ritorno

Tipo Descrizione
Un numero.NaN se non viene trovato alcun numero intero.


Supporto browser

parseFloat() è una funzione ECMAScript1 (ES1).

ES1 (JavaScript 1997) è completamente supportato in tutti i browser:

Chrome IE Edge Firefox Safari Opera
Yes Yes Yes Yes Yes Yes

Altri esempi

Analizza valori diversi:

parseInt("10", 10);
parseInt("010");
parseInt("10", 8);
parseInt("0x10");
parseInt("10", 16);