如何在javascript中操纵数组的值？

Question

I'm quite new to Javascript and I have the following javascript array in an AJAX Request that contains the following:

["12435|#CANON#DEVICE#|#50#|Machine Detail|Details|SampleRow|FALSE|FALSE|FALSE|FALSE|FALSE|FALSE|TRUE"]

I wanna manipulate the TRUE and FALSE value. If they're in uppercase, I want to make it lowercase. Any idea how I can do it?

Answer 1

If you want to modify the list you could just loop through all of its items, modify the value and set it to the same index of the list. (You don't need to set it if you are dealing with objects).

 var list = ["12435|#CANON#DEVICE#|#50#|Machine Detail|Details|SampleRow|FALSE|FALSE|FALSE|FALSE|FALSE|FALSE|TRUE"]; list.forEach(function(item, index) { list[index] = item.replace(/(TRUE|FALSE)/g, function(upperCase) { return upperCase.toLowerCase(); }); }); console.log(list); 

Same thing using a for loop:

 var list = ["12435|#CANON#DEVICE#|#50#|Machine Detail|Details|SampleRow|FALSE|FALSE|FALSE|FALSE|FALSE|FALSE|TRUE"]; for (var index = 0; index < list.length; index++) { list[index] = list[index].replace(/(TRUE|FALSE)/g, function(upperCase) { return upperCase.toLowerCase(); }); } console.log(list); 

If you want to create a copy you could do:

 var list = ["12435|#CANON#DEVICE#|#50#|Machine Detail|Details|SampleRow|FALSE|FALSE|FALSE|FALSE|FALSE|FALSE|TRUE"]; var newList = list.map(function(item) { return item.replace(/(TRUE|FALSE)/g, function(upperCase) { return upperCase.toLowerCase(); }); }); console.log(newList); 

The above scripts will also transform something like ["THIS IS NOT TRUE|TRUE|FALSE"] to ["THIS IS NOT true|true|false"] . If you do not want that you should use this regex instead /(^|(?<=\\|))(TRUE|FALSE)(\\||$)/ ie:

 var list = ["12435|#CANON#DEVICE#|#50#|Machine Detail|Details|SampleRowFALSE|FALSE|FALSE|FALSE|FALSE|FALSE|FALSE|TRUE"]; for (var index = 0; index < list.length; index++) { list[index] = list[index].replace(/(^|(?<=\\|))(TRUE|FALSE)(\\||$)/g, function(upperCase) { return upperCase.toLowerCase(); }); } console.log(list); 

Answer 2

Just use replace with map :

 const arr = ["12435|#CANON#DEVICE#|#50#|Machine Detail|Details|SampleRow|FALSE|FALSE|FALSE|FALSE|FALSE|FALSE|TRUE"]; const res = arr.map(e => e.replace(/(TRUE|FALSE)/g, m => m.toLowerCase())); console.log(res); 

Answer 3

 const arrayString = ["12435|#CANON#DEVICE#|#50#|Machine Detail|Details|SampleRow|FALSE|FALSE|FALSE|FALSE|FALSE|FALSE|TRUE"] const arrayOfValues = arrayString[0].split('|').map(val => { if(val === 'TRUE' || val === 'FALSE') { return val.toLowerCase(); } else { return val; } }); console.log(arrayOfValues) 

Answer 4

Use RegEx as you have been told before. If you want to learn more about this look at: W3Schools

One solution could be like this:

  var ajaxResponse = "12435|#CANON#DEVICE#|#50#|Machine Detail|Details|SampleRow|FALSE|FALSE|FALSE|FALSE|FALSE|FALSE|TRUE"; ajaxResponse = ajaxResponse.replace(/FALSE/g, "false"); ajaxResponse = ajaxResponse.replace(/TRUE/g, "true"); console.log(ajaxResponse);