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HomeWeb Front-endFront-end Q&ALet's talk about the commonly used inequality sign operations in jquery

As web page interactions become more and more complex, many JavaScript libraries and plug-ins have appeared in the field of web page production, making it easier for developers to implement various functions. Among them, jQuery is the most famous one, it is simple to use but powerful. This article will introduce the commonly used inequality sign operations in jQuery.

Equality and inequality

In JavaScript, comparison operators include equality operators (==) and inequality operators (!=). When comparing two values, the equality operator converts them to the same type and then compares their values; the unequal operator converts them to the same type and then checks whether they are equal.

For example:

console.log(5 == "5"); // true
console.log(5 != "5"); // false
console.log(5 == 5.0); // true
console.log(5 != 5.0); // false

Strict equality and inequality

In addition to the equality and inequality operators, there is a set of operators that can perform more strict comparisons, namely strict Equality operator (===) and strict inequality operator (!==).

The strict equality operator returns true only if the types are the same and the values ​​are equal, otherwise it returns false. The result of the strict inequality operator is the opposite.

For example:

console.log(5 === "5"); // false
console.log(5 !== "5"); // true
console.log(5 === 5.0); // true
console.log(5 !== 5.0); // false

Inequality operator

The inequality operator in jQuery includes:

  • :not() Selector
  • .not() Method

:not() Selector

: The not() selector is used to select elements that do not match the specified selector. It can be used to filter out some unnecessary elements.

For example, the following code will select all elements except the div element:

$(":not(div)").css("color", "red");

.not() Method

# The

##.not() method is a method of the jQuery object that removes elements matching the selector from the current jQuery object. This method is also used to filter jQuery collections and find elements in jQuery collections.

For example, the following code will select all elements except the element with the class name

important:

$(".some-class").not(".important").css("background-color", "gray");
Summary

The inequality operator is in jQuery plays a very important role in helping developers filter and select elements on the page more easily. Choosing the right operator can also greatly improve the performance of the page and avoid unnecessary DOM operations.

I hope this article will be helpful to readers, and I also hope that I can learn and master the various operators in jQuery more comprehensively.

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