哪个在JavaScript String中更有效

Question

这两者中更有效的手段可以提供更快的输出 第一个

outString =  "My First String";
outString += "My Second String";
outString += "My Third String";
outString += "My Fourth String";
outString += "My Fifth String";
myFinalString = outString;

或第二个

outString =  "My First String"
          + "My Second String"
          + "My Third String"
          + "My Fourth String"
          + "My Fifth String";
myFinalString = outString;

在其中一个屏幕中我制作的字符串超过100行，那么你会建议哪个？

Answer 1

在Chrome中，性能几乎完全相同：

Firefox也显示了类似的结果，所以我不担心你使用哪种语法。

JSPerf结果：https://jsperf.com/javascript-string-test