javascript logical OR (||)

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9<! -8      
         Logical OR (||) personal understanding:
 10          Prerequisites:
 . 11          - Logical or decision sequence: from left to right;
 12 is          - as long as it is no longer true encountered down directly returns a true value of the first;
 13 is          - in before she encountered, would have been down the judgment, if the last one is false / null / undefined / NaN, it returns the last false / null / undefined / NaN values of
 14          number 1) operations are boolean,
 15           1 true / multi true / all true: returns to true
 16           full false: returns to false
 . 17          number 2) is operated as a multi-mixed type (expression, and other Boolean type)
 18 is           1 in real / real multiple / all true: returns a true value of
 19           full false / null / undefined / NaN: returns the last value
 20 is       -> 
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24          var A = . 1 , B = " 2 " , C = 0 , D = " ABC " , E = "" , F, G = A - D;
 25          / * Logical OR: bool * / 
26 is          the console.log ((ab & ) || (A - ABC)); // -1, ab & true, the determination is no longer down 27         the console.log (A > 10 || A < 10 ); // true, A> 10 false, a <10 true true true returns 1
  
28          / * Logical OR: Mixed * / 
29          the console.log (C || A || B || D); // . 1, a first return true. 1 = A 
30          the console.log (C || E ||  null  || undefined || G); // NaN3, false returns the last full prosthesis 
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33 is  </ HTML >

 

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Origin www.cnblogs.com/vinson-blog/p/11989519.html