44 lines
1.1 KiB
JavaScript
44 lines
1.1 KiB
JavaScript
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console.log("====================object.keys, values, entries====================")
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console.log("Object function, you must call Object.keys but not obj.keys")
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console.log("Object.keys(obj) - returns an array of keys")
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console.log("Object.values(obj) - returns an array of values")
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console.log("Object.entries(obj) - returns an array of [key, value] pair")
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console.log("Object.fromEntries(array) - on the resulting array to turn it back into an object")
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let prices = {
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banana : 4,
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orange : 2,
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meat : 1,
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}
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console.log(`Object.entries(prices): ${Object.entries(prices)}`)
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let doubleprices = Object.fromEntries(
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Object.entries(prices).map(entry => [entry[0], entry[1] * 2])
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);
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console.log(`Object.entries(doubleprices): ${Object.entries(doubleprices)}`)
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Object.values(prices).reduce((sum, cur)=> sum+cur, 0)
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function sumSalaries(salaries ){
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return Object.values(salaries).reduce((sum, cur) => sum + cur, 0);
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}
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let salaries = {
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"John": 100,
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"Pete": 300,
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"Mary": 250
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};
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console.log(sumSalaries(salaries));
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function count(user){
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return Object.keys(user).length;
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}
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let user = {
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name : "John",
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age: 30
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};
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console.log(count(user)); |