var A == var B == 1寻找真理.不工作.可能吗?

jam*_*non 1 javascript

不确定这是可行的,但我正在寻找一个真值回报,例如.. var A = 100; var B = 100;

(A == B == 100) 
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我认为这会回归真实.因为A == B(它们都是100)并且因此它们都等于100.

但它总是错误的.

编辑:::谢谢,是的 - 我很感激回复...我希望有一些漂亮的shorhand比做(A === 100)&&(B === 100)等......但是非常感谢.

Udo*_*ein 13

要么评估为

(A == B) == 100
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或者作为

A == (B == 100)
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在这两种情况下,您都将布尔值与100进行比较.这当然总是假的.你要

(A==100) && (B==100)
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要查看发生了什么,您可能希望将下面的示例作为JSFiddle运行:

var A = 100;
var B = 100;

alert("B == 100: " + (B == 100));
alert("A == (B == 100):" + (A == (B == 100)));
alert("A == B:" + (A == B));
alert("(A == B) == 100:" + ((A == B) == 100));
alert("A == B == 100):" + (A == B == 100));
alert("(A == 100) && (B == 100):" + ((A == 100) && (B == 100)));
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