JS 运算符

JS 运算符

---

运算符 = 用于赋值。

运算符 + 用于加值。

---

JavaScript 算术运算符

+ - * /	% ++ --

JavaScript 赋值运算符

= += -=	*= /= %=

---

用于字符串的 + 运算符

txt1="What a very";
txt2="nice day";
txt3=txt1+txt2;

 //"What a verynice day"
 
 txt1="What a very ";
txt2="nice day";
txt3=txt1+txt2;

//"What a very nice day"

txt1="What a very";
txt2="nice day";
txt3=txt1+" "+txt2;

//"What a very nice day"

---

对字符串和数字进行加法运算

x=5+5;
document.write(x);

x="5"+"5";
document.write(x);

x=5+"5";
document.write(x);

x="5"+5;
document.write(x);

10/55/55/55

规则是：
如果把数字与字符串相加，结果将成为字符串。