JS Reference

JS by Category JS by Alphabet

JavaScript

JS Array JS Boolean JS Classes JS Date JS Error JS Global JS JSON JS Math JS Number JS Operators JS RegExp JS Statements JS String

Window

Window Object Window Console Window History Window Location Window Navigator Window Screen

HTML DOM

DOM Document DOM Element DOM Attributes DOM Events DOM Event Objects DOM HTMLCollection DOM Style
alignContent alignItems alignSelf animation animationDelay animationDirection animationDuration animationFillMode animationIterationCount animationName animationTimingFunction animationPlayState background backgroundAttachment backgroundColor backgroundImage backgroundPosition backgroundRepeat backgroundClip backgroundOrigin backgroundSize backfaceVisibility border borderBottom borderBottomColor borderBottomLeftRadius borderBottomRightRadius borderBottomStyle borderBottomWidth borderCollapse borderColor borderImage borderImageOutset borderImageRepeat borderImageSlice borderImageSource borderImageWidth borderLeft borderLeftColor borderLeftStyle borderLeftWidth borderRadius borderRight borderRightColor borderRightStyle borderRightWidth borderSpacing borderStyle borderTop borderTopColor borderTopLeftRadius borderTopRightRadius borderTopStyle borderTopWidth borderWidth bottom boxShadow boxSizing captionSide caretColor clear clip color columnCount columnFill columnGap columnRule columnRuleColor columnRuleStyle columnRuleWidth columns columnSpan columnWidth counterIncrement counterReset cursor direction display emptyCells filter flex flexBasis flexDirection flexFlow flexGrow flexShrink flexWrap cssFloat font fontFamily fontSize fontStyle fontVariant fontWeight fontSizeAdjust height isolation justifyContent left letterSpacing lineHeight listStyle listStyleImage listStylePosition listStyleType margin marginBottom marginLeft marginRight marginTop maxHeight maxWidth minHeight minWidth objectFit objectPosition opacity order orphans outline outlineColor outlineOffset outlineStyle outlineWidth overflow overflowX overflowY padding paddingBottom paddingLeft paddingRight paddingTop pageBreakAfter pageBreakBefore pageBreakInside perspective perspectiveOrigin position quotes resize right scrollBehavior tableLayout tabSize textAlign textAlignLast textDecoration textDecorationColor textDecorationLine textDecorationStyle textIndent textOverflow textShadow textTransform top transform transformOrigin transformStyle transition transitionProperty transitionDuration transitionTimingFunction transitionDelay unicodeBidi userSelect verticalAlign visibility width wordBreak wordSpacing wordWrap widows zIndex

Web APIs

API Console API Fullscreen API Geolocation API History API MediaQueryList API Storage

HTML Objects

<a> <abbr> <address> <area> <article> <aside> <audio> <b> <base> <bdo> <blockquote> <body> <br> <button> <canvas> <caption> <cite> <code> <col> <colgroup> <datalist> <dd> <del> <details> <dfn> <dialog> <div> <dl> <dt> <em> <embed> <fieldset> <figcaption> <figure> <footer> <form> <head> <header> <h1> - <h6> <hr> <html> <i> <iframe> <img> <ins> <input> button <input> checkbox <input> color <input> date <input> datetime <input> datetime-local <input> email <input> file <input> hidden <input> image <input> month <input> number <input> password <input> radio <input> range <input> reset <input> search <input> submit <input> text <input> time <input> url <input> week <kbd> <label> <legend> <li> <link> <map> <mark> <menu> <menuitem> <meta> <meter> <nav> <object> <ol> <optgroup> <option> <output> <p> <param> <pre> <progress> <q> <s> <samp> <script> <section> <select> <small> <source> <span> <strong> <style> <sub> <summary> <sup> <table> <tbody> <td> <tfoot> <th> <thead> <tr> <textarea> <time> <title> <track> <u> <ul> <var> <video>

Other References

CSSStyleDeclaration JS Conversion


JavaScript String indexOf()

Exemplos

Pesquise uma string por "welcome":

let text = "Hello world, welcome to the universe.";
let result = text.indexOf("welcome");

Pesquise uma string por "Bem-vindo":

let text = "Hello world, welcome to the universe.";
let result = text.indexOf("Welcome");

Encontre a primeira ocorrência de "e":

let text = "Hello world, welcome to the universe.";
text.indexOf("e");

Encontre a primeira ocorrência de "e", começando na posição 5:

let text = "Hello world, welcome to the universe.";
text.indexOf("e", 5);

Encontre a primeira ocorrência de "a":

let text = "Hello world, welcome to the universe.";
text.indexOf("a");

Definição e uso

O indexOf()método retorna a posição da primeira ocorrência de um valor em uma string.

O indexOf()método retorna -1 se o valor não for encontrado.

O indexOf()método diferencia maiúsculas de minúsculas.


Sintaxe

string.indexOf(searchvalue, start)

Parâmetros

Parameter Description
searchvalue Required.
The string to search for.
start Optional.
The position to start from (default is 0).

Valor de retorno

Modelo Descrição
Um númeroA primeira posição em que o valor de pesquisa ocorre.
-1 se nunca ocorrer.


A diferença entre
String indexOf() e String search()

O indexOf()método não pode pesquisar em uma expressão regular.

O search()não pode receber um argumento de posição inicial.



Suporte ao navegador

indexOf() é um recurso ECMAScript1 (ES1).

ES1 (JavaScript 1997) é totalmente suportado em todos os navegadores:

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