The accuracy of JavaScript decimal arithmetic will be lost, which will bring a lot of inconvenience to the project. Please have a look at the following script first:

javascript，javascript

& ltscript type = " text/JavaScript " language = " JavaScript " & gt；

alert( 1/3)； //popup: 0.3300000000005

Early warning (0.09999999+0.0000001); //popup: 0.09999

alert(-0.09999999-0.000000 1)； //popup:-0.0000.00000005

alert(0.0 12345 * 0.0000 1)； //popup: 1.9999e-8。

alert(0.00000 1/0.000 1)； //Pop-up window: 0.56860.56860888886

& lt/script & gt；

According to the normal calculation, except the first line (because it can't be divided by itself), everything else should get accurate results, but from the pop-up results, we find that it is not the correct result we want. In order to solve the problem of inaccurate floating-point number operation, we upgrade the number to integer (10 to the x power) before the operation, and then downgrade it (0. 1 to the x power) after the operation. Now collect and paste it here for later use.

javascript，javascript

//addition

number . prototype . add = function(arg){

var r 1，r2，m；

Please try {r 1=this.toString (). Split (".") [1]. length} catch (e) {r1= 0}

Please try {r2=arg.toString (). Split (".") [1]. Length} Capture (e){r2=0}

m=Math.pow( 10，Math.max(r 1，r2))

return (this*m+arg*m)/m

}

//subtraction

number . prototype . sub = function(arg){

Return this.add (-arg);

}

//multiplication

Number.prototype.mul = function (arg)

{

var m=0，s 1=this.toString()，S2 = arg . tostring()；

Please try {m+= s1.split (".") [1]. length} catch (e) {}

Try {m+= s2.split (".") [1]. length} catch (e) {}

Returns the number (s 1.replace (".","")) * number (s2.replace (".","")) /Math.pow( 10, m).

}

//division

number . prototype . div = function(arg){

var t 1=0，t2=0，r 1，R2；

Please try {t 1=this.toString (). Split (".") [1].length}catch(e){}

Please try {t2=arg.toString (). Split (".") [1].length}catch(e){}

Use (mathematics) {

r 1=Number(this.toString()。 Replace (".",""))

r2=Number(arg.toString()。 Replace (".",""))

return(r 1/R2)* pow( 10，T2-t 1)；

}

}

test

javascript，javascript

& ltscript type = " text/JavaScript " language = " JavaScript " & gt；

Alarm (number: 0.09999999). Plus (0.00000001)); //popup: 0. 1

//Note that if it is a negative number, it must be converted by numbers first, otherwise the result will be incorrect.

Alarm (number (-0.09999999). sub(0.0000000 1))； //popup: -0. 1

Alarm (number (0.0 12345). mul(0.00000 1))； //popup: 1.2345e-8

Alarm (number (0.00000 1). div(0.000 1))； //popup: 0.0 1

& lt/script & gt；