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TypeScript - create array
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This article will show you how to create an array in TypeScript.
Quick solution:
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const arrayName: elementType[] = [element1, element2, element3, elementN];
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const myArray: string[] = ['Tom', 'Kate', 'Mary'];2
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console.log(myArray);Output:
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[ 'Tom', 'Kate', 'Mary' ]The above creation of an array can also be written as follows:
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const myArray: string[] = ['Tom', 'Kate', 'Mary'];2
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console.log(myArray);Output:
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[ 'Tom', 'Kate', 'Mary' ]or:
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const myArray: string[] = [];2
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myArray[0] = 'Tom';4
myArray[1] = 'Kate';5
myArray[2] = 'Mary';6
// null on 3rd and 4th positions7
myArray[5] = 'John';8
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console.log(myArray);Output:
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[ 'Tom', 'Kate', 'Mary', <2 empty items>, 'John' ]Note: this approach will cause automatic array resizing on assigning new indexes - by assigning non consecutive indexes, the array will be filled in unused areas with
nullvalues.
or:
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const myArray: string[] = Array(3);2
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myArray[0] = 'Tom';4
myArray[1] = 'Kate';5
myArray[2] = 'Mary';6
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console.log(myArray);Output:
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[ 'Tom', 'Kate', 'Mary' ]Note: this approach allocates necessary array space during array creation - not necessary resize in memory later.
or:
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const myArray: string[] = new Array('Tom', 'Kate', 'Mary');2
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console.log(myArray);Output:
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[ 'Tom', 'Kate', 'Mary' ]Note: the constructor-based approach used a much less frequent approach.
