jquery remove spaces and empty lines

With the development of the Internet, more and more websites use front-end frameworks, among which jquery is one of the most popular front-end frameworks. However, websites often contain a large amount of code, and spaces and empty lines in the code may affect the standardization and performance of the website. Therefore, in jquery, it is important to remove spaces and empty lines.

1. Remove spaces with jquery

There may be extra spaces in the front-end code of some websites. If these spaces cannot be cleared, it may greatly increase the loading time of the website. At this point, you can use jquery to remove extra spaces. jquery provides three methods: $.trim(), $.grep() and $.map().

1.$.trim() method

$.trim() method can remove spaces at both ends of a string. For example:

var str = " hello world ";
alert($.trim(str)); //输出 “hello world”

2.$.grep() method

$.grep() method can filter the array according to the conditions and remove spaces from the array elements. For example:

var arr = [" hello ", " world ", " ", " javascript ", ""];
var resultArr = $.grep(arr, function(value, index) {
    return value != "" && value != " ";
});
alert(resultArr); //输出 “hello,world,javascript”

3.$.map() method

$.map() method can filter the array according to the conditions and remove spaces from the array elements. For example:

var arr = ["hello ", " world", " javascript ", "  "];
var resultArr = $.map(arr, function(value, index) {
    return $.trim(value);
});
alert(resultArr); //输出 “hello,world,javascript”

2. jquery removes blank lines

Some websites have many blank lines in their front-end code. These blank lines are incomprehensible and make the code more difficult to read. jquery provides a method to remove blank lines, the $.grep() method. For example:

var arr = [" hello
", "
 world 
", "

 java
script 
"];
var resultArr = $.grep(arr, function(value, index) {
    return $.trim(value) != "";
});
alert(resultArr); //输出 “hello world javascript”

In this example, the $.trim() function is used to remove the prefix and suffix spaces of each element, and the $.grep() function filters the array and removes all empty ( elements excluding prefix and suffix spaces).

Summary

In jquery, it is very important to remove spaces and empty lines, because this affects the standardization and performance of the website. You can use the $.trim(), $.grep() and $.map() methods to remove excess spaces, and the $.grep() method can be used to remove blank lines. No matter which method is used, the front-end code of the website can be more standardized and the loading speed of the website can be improved.

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