JavaScript statements and the operator

• One yuan increment and decrement operations, unary operators for addition and subtraction Number conversion function for non-numeric type are
• Boolean operators in case where the operand is not a Boolean return value according to the situation
• Multiplicative division operator in the case where the processing of special value
  • A / * s = NaN
  • Infinity * Infinity = Infinity,Infinity / Infinity =NaN
  • Infinity * / 0 = NaN
  • Infinity * A = Infinity
  • If A is not a value, executes Number The (A) conversion
• Type equality operator performs converted, strict equality operator does not perform the type of conversion. null == undefined
• for-in statement is used to enumerate the object properties