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do...while

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This feature is well established and works across many devices and browser versions. Its been available across browsers since 2015 ..

do...while , , . , .

In this article

let result = "";
let i = 0;

do {
  i = i + 1;
  result = result + i;
} while (i < 5);

console.log(result);
// Expected output: "12345"


do
   
while ();

, , . , ({ ... }).

, . , . , , do...while.

do...while

, do...while , i 5.

HTML

html
<div id="example"></div>

JavaScript

js
var result = "";
var i = 0;
do {
  i += 1;
  result += i + " ";
} while (i > 0 && i < 5); //   ,  i == 0,    ,     
document.getElementById("example").innerHTML = result;

Specification
ECMAScript 2027 LanguageSpecification
# sec-do-while-statement

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  1. JavaScript
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    75. SyntaxError: private fields can't be deleted
    76. SyntaxError: property name __proto__ appears more than once in object literal
    77. SyntaxError: raw bracket is not allowed in regular expression with unicode flag
    78. SyntaxError: redeclaration of formal parameter "x"
    79. SyntaxError: reference to undeclared private field or method #x
    80. SyntaxError: rest parameter may not have a default
    81. SyntaxError: return not in function
    82. SyntaxError: setter functions must have one argument
    83. SyntaxError: string literal contains an unescaped line break
    84. SyntaxError: super() is only valid in derived class constructors
    85. SyntaxError: tagged template cannot be used with optional chain
    86. SyntaxError: Unexpected '#' used outside of class body
    87. SyntaxError: Unexpected token
    88. SyntaxError: unlabeled break must be inside loop or switch
    89. SyntaxError: unparenthesized unary expression can't appear on the left-hand side of '**'
    90. SyntaxError: use of super property/member accesses only valid within methods or eval code within methods
    91. SyntaxError: Using //@ to indicate sourceURL pragmas is deprecated. Use //# instead
    92. :
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    98. TypeError: "x" is read-only( : "x" )
    99. TypeError: already executing generator
    100. TypeError: BigInt value can't be serialized in JSON
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    104. TypeError: can't convert BigInt to number
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    107. TypeError: can't delete non-configurable array element( : )
    108. TypeError: can't redefine non-configurable property "x"
    109. TypeError: can't set prototype of this object
    110. TypeError: can't set prototype: it would cause a prototype chain cycle
    111. TypeError: cannot use 'in' operator to search for 'x' in 'y'( 'in' 'x' 'y')
    112. TypeError: class constructors must be invoked with 'new'
    113. TypeError: cyclic object value
    114. TypeError: derived class constructor returned invalid value x
    115. TypeError: getting private setter-only property
    116. TypeError: Initializing an object twice is an error with private fields/methods
    117. TypeError: invalid 'instanceof' operand 'x'( : '' '')
    118. TypeError: invalid Array.prototype.sort argument (TypeError: Array.prototype.sort argument)
    119. TypeError: invalid assignment to const "x"( const "x")
    120. TypeError: Iterator/AsyncIterator constructor can't be used directly
    121. TypeError: matchAll/replaceAll must be called with a global RegExp
    122. TypeError: More arguments needed
    123. TypeError: "x" has no properties
    124. TypeError: property "x" is non-configurable and can't be deleted( "x" )
    125. TypeError: Reduce of empty array with no initial value( : )
    126. TypeError: setting getter-only property "x"( "x")
    127. TypeError: WeakSet key/WeakMap value 'x' must be an object or an unregistered symbol
    128. X.prototype.y called on incompatible type
    129. URIError: malformed URI sequence
    130. Warning: -file- is being assigned a //# sourceMappingURL, but already has one
    131. Warning: unreachable code after return statement
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