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array.concat(value1, value2, value3,...valuen)

Arguments

value1, ...valuen

A list of expressions to be added to the end of array as new elements.

Returns

A new array containing all the elements of array, followed by the elements value1, ...valuen.

Description

The concat( ) method returns a new array created by appending new elements to the end of an existing array. The original array is left unchanged. Use the push( ), splice( ), or shift( ) method to modify the original array.

If an array is used as an argument to concat( ), each element of that array is appended separately. That is, the result of arrayX.concat(arrayY) will be an array formed by appending each element of arrayY to the end of arrayX. The resulting array will have a length equal to arrayY.length + arrayX.length. Nested arrays, however, are not similarly flattened.

Example

// Create an array
myListA = new Array("apples", "oranges");
   
// Set myListB to ["apples", "oranges", "bananas"]
myListB = myListA.concat("bananas");     
   
// Create another new array
myListC = new Array("grapes", "plums");
   
// Set myListD to ["apples", "oranges", "bananas", "grapes", "plums"]
myListD = myListB.concat(myListC);
   
// Set myListA to ["apples", "oranges", "bananas"]
myListA = myListA.concat("bananas");
   
// Create an array
settings  = ["on", "off"];
// Append an array containing a nested array
options = settings.concat(["brightness", ["high", "medium", "low"]]);
// Sets options to: ["on", "off", "brightness", ["high", "medium", "low"]] 
// not: ["on", "off", "brightness", "high", "medium", "low"]

See Also

Array.push( ), Array.shift( ), Array.splice( ); Section 11.7.3.4

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