Javascript Methods short discussion

Array Methods

1.concat()

concat() is an array javascript method using for adding two or more arrays. It returns a new array for adding two or more arrays. You use concat method parameter in the second array name or using direct value. It is added the old/first array and returns a new array.

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2.find()

find() is the javascript array method. it is using to search an array element in the array. The find method parameter you can provide a callback function then set your condition in the callback function. After the condition is true return this element otherwise return undefined.

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3.findIndex()

findIndex method using for find array element index, you can provide a callback function in findIndex parameter then set the condition in callback function after matching the condition then return 1 otherwise return -1

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4.filter()

filter method using for filter arrays. filter parameter must provide a callback function then set your condition in a callback function. Check the condition of all array elements. Then With those element conditions that have been true then return a new array for this element.

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5.pop()

pop method using for the array the last element removed. If you use the pop method then remove the last element in your array and return this element.

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6.shift()

shift method using for the array first element removed. If you use the shift method then remove the first element in your array and return this element.

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7.push()

push method using to add a new element in the array and a new element is added to the last element in the array and return this array length.

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8.unshift()

unshift method using to add a new element in the array and a new element is add the first element in the array and return this array length.

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9.reverse()

reverse method is using for reverse array elements. If you use this method reverse all elements in your array and return this array.

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10.join()

join method is using for converted all array elements to string. you use this method then return a string for all elements. You do not use any parameter in the join method parameter then add a comma by default in the middle for all elements and return this string, or you use an empty string then return only all elements.

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String Methods

1.charAt()

charAt method is using for a letter in the string. You provide a parameter then return this index letter or by default return, the first index letter but your provided parameter is bigger than the array length then return an empty string.

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2.concat()

concat() method used for adding two or more strings. It returns a new string for adding two or more strings. You use concat method parameter in the second variable name or using direct value. It is added the old/first string and returns a new string.

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