Several ways to remove spaces in JavaScript_javascript tips

Method 1:
Personally I think this is the best method. It uses regular expressions, which is the core principle.
Secondly, this method uses JavaScript’s prototype attribute

In fact, if you don’t use this attribute, you can also use a function. But it is more convenient to use it this way.
Let’s take a look at how this attribute is used.

Return the object A reference to the type prototype.

objectName.prototype
objectName parameter is the name of the object.

Description
Use the prototype attribute to provide a set of basic functions of the object's class. New instances of an object "inherit" the operations assigned to the object's prototype. For example, you want to add a method to an Array object that returns the value of the largest element in the array. To accomplish this, declare the function, add it to Array.prototype, and use it.

Copy code The code is as follows:

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 this code is executed, y saves the maximum value in the array x, or 6.

All JScript internal objects have a read-only prototype attribute. You can add functionality to a prototype as in this example, but the object cannot be assigned a different prototype. However, user-defined objects can be assigned to new prototypes.
The list of methods and properties for each internal object in this language reference indicates which ones are part of the object's prototype and which ones are not.
The following is the original code

Copy the code The code is as follows:

s matches any whitespace character, including spaces, tabs, form feeds, etc. Equivalent to [fnrtv].

Please remember that it is lowercase s


Method 2:

Since the method of use is simple, I will not give an example here.

Copy code The code is as follows://javascript function to remove spaces

function LTrim(str){ //Remove string Header space

var i;
for(i=0;i if(str.charAt(i)!=" "&&str.charAt(i)!=" ") break;
}
str = str.substring(i,str.length);
return str;
}
function RTrim(str){
var i;
for(i=str.length-1 ;i>=0;i--){
if(str.charAt(i)!=" "&&str.charAt(i)!=" ") break;
}
str = str. substring(0,i 1);
return str;
}
function Trim(str){

return LTrim(RTrim(str));

}



Method 3:

This method writes functions together and achieves different effects by passing different parameters

JavaScript Trim Function <title> </title> String removal whitespace function in JavaScript (custom):