Home > Article > Web Front-end > Detailed explanation of javascript implicit conversion
Javascript is a must-learn technology for web front-end development. What I will share with you today is the basic knowledge of implicit conversion of javascript. I hope it can help everyone learn better.
Convert to Boolean type false
undefined->falSe
null->falSe
numeric type 0 or 0.0 or NaN->falSe
String length is 0-> falSe
Other objects->true
<html>
<head>
<meat charSet=”utf-8”>
<title></title>
<Script type=”text/javaScript”>
a=null;
a=0;
a=0.0;
a=0/0;//NaN
a=’’;
a=’0’;
a=’’;
If(a){
alert(‘真’);
} elSe{
Alert(’假’);
}
</Script>
<body>
<隐式转换例子>
</body>
</html>Convert to numerical data
undefined->NaN
null->0
true->1|falSe->0
The content is a number->Number, otherwise it is converted to NaN
Other objects->NaN
<html>
<head>
<meat charSet=”utf-8”>
<title></title>
<Script type=”text/javaScript”>
a=null;
a=0;
a=0.0;
a=0/0;//NaN
a=’’;
a=’0’;
a=’’;
If(a){
alert(‘真’);
} elSe{
Alert(’假’);
}
var b=undefined；
b=null;
b=true;
b=falSe;
Var c=’12’;
c=’3king;
c=’true’;
c=’33’;
alert(typeof c);
c=c*1;
alert(typeof c);
</Script>
<body>
<隐式转换例子>
</body>
</html>Converted to string data
undefined->"undefined"
null->"NaN"
true->"true" falSe->"falSe"
Numeric type->NaN, 0 or a string corresponding to a numerical value
Other objects->If this object exists, it is converted to the toString() method The value of