JavaScript to remove whitespace various methods summary

Last Update:2017-01-13 Source: Internet

Author: User

Tags rtrim trim

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Method One:

Personally think the best way. Using regular expressions, this is the core principle.
Second, this method uses the prototype properties of JavaScript

In fact, you do not use this property can be implemented using the function. But this is easier to use.
Let's take a look at how this property is used.

Returns a reference to the object type prototype.

Objectname.prototype
The objectname parameter is the name of the object.

Description
Use the prototype property to provide a set of basic functions for the object's class. The operation of the new instance of the object, "inherit", gives the object a prototype.

For example, to add a method that returns the maximum element value in an array for the array object. To do this, declare the function, add it to the Array.prototype, and use it.

The code is as follows

Copy Code

function Array_max () {

var i, max = this[0];

for (i = 1; i < this.length; i++)

{

if (Max < this[i])

max = This[i];

}

return Max;

}

Array.prototype.max = Array_max;

var x = new Array (1, 2, 3, 4, 5, 6);

var y = X.max ();

After the code executes, Y saves the maximum value in the array x, or says 6.

All JScript internal objects have read-only prototype properties. You can add functionality to the prototype as in this example, but the object cannot be given a different prototype. However, user-defined objects can be assigned to a new prototype.

The list of methods and attributes for each internal object in the language reference indicates which parts of the object's prototype and which are not.

The following is the original code

Program code

The code is as follows

Copy Code

<!--

Source: Online Collection

Made by Yaosansi 2005-12-02

For more visit http://www.111cn.net

Trim (), Ltrim (), RTrim ()

String.prototype.Trim = function ()

{

Return This.replace (/(^s*) | ( s*$)/g, "");

}

String.prototype.LTrim = function ()

{

Return This.replace (/(^s*)/g, "");

}

String.prototype.RTrim = function ()

{

Return This.replace (/(s*$)/g, "");

}

-->

</SCRIPT>

Let's take a look at what "s/s represents in the JS script.

s matches any whitespace character, including spaces, tabs, page breaks, and so on. equivalent to [FNRTV].

Please bear in mind that the lowercase s

jquery Delete Space

The code is as follows	Copy Code
$.trim (str)

Regular substitution space

The code is as follows

Copy Code

<title> IE9 js All kinds of go to space Daquan </title>
<script>
function Clearspace (Inputo) {
var Valuetext=inputo.value;
Remove space before and after
var text1=valuetext.replace (/^s+/, ""). Replace (/s+$/, "");
Remove all spaces
var text2=valuetext.replace (/[]/g, "");
Remove Front space
var text3=valuetext.replace (/^s+/, "");
Remove space after
var text4=valuetext.replace (/s+$/, "");
Alert ("= =" +text1+ "= =");
Alert ("= =" +text2+ "= =");
Alert ("= =" +text3+ "= =");
Alert ("= =" +text4+ "= =");
}
</script>
<body>
<input type= "text" id= "Appno" onblur= "clearspace (this);"/>
</body>

Traverse Delete Space

code is as follows

copy code

//To be invoked by the user
Function Trim (s) {
return TrimRight (Trimleft (s));
}
//Remove the left blank
function Trimleft (s) {
if (s = = null) {
Return];
}
var whitespace = new String ("TNR");
var str = new String (s);
if (whitespace.indexof (Str.charat (0))!=-1) {
var j=0, i = str.length;
while (J < i && Whitespace.indexof (Str.charat (j))!=-1) {
J + +;
}
str = str.substring (j, I);
}
return str;
}
//Remove the blank www.111cn.net
function trimright (s) {
if (s = = null) return "";
var whitespace = new String ("TNR");
var str = new String (s);
if (Whitespace.indexof (Str.charat (str.length-1))!=-1) {
var i = str.length-1;
while (i >= 0 && whitespace.indexof (str.charat (i))!=-1) {
i--;
}
str = str.substring (0, i+1);
}
return str;
}

This article is an English version of an article which is originally in the Chinese language on aliyun.com and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or complaint, to info-contact@alibabacloud.com. A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.

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