为什么开发者控制台对相同的数据输入给出不同的结果？

Question

为什么开发者控制台对相同的数据输入给出不同的结果？下面是我在 Chrome 开发者控制台中检查的代码。我很困惑如何提供不同的输出。

    // First time

    var a = [1, 2, 3];

    var b = [1, 2, 3];

    var c = "1,2,3";

    a == c; // true

    b == c; // true

    a == b; // false

    //Second time

    console.log(a == c);

    console.log(b == c);

    console.log(a == b);

    a = [1, 2, 3];

    b = [a, 2, 3];

    c = "1, 2, 3";

    console.log(a == c);  //false

    console.log(b == c);  //false

    console.log(a == b); //false

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Answer 1

// First timevar a = [1, 2, 3];var b = [1, 2, 3];var c = "1,2,3";a == c; // trueb == c; // truea == b; // false//Second timeconsole.log(a == c);console.log(b == c);console.log(a == b);a = [1, 2, 3];b = [a, 2, 3];c = "1, 2, 3";console.log(a == c);  //falseconsole.log(b == c);  //falseconsole.log(a == b); //false第二组看起来像这样：a = [1, 2, 3];b = [[1,2,3],2,3]; -> Jagged Array;c = "1,2,3"

Answer 2

b = [1, 2, 3]; // first b = [a, 2, 3]; // second数组的第一个元素不同ps避免'=='并在生产中使用'==='。

Answer 3

您第二次执行的所有值都是错误的，因为没有一个值是相等的。var c = "1,2,3" 与 c = "1, 2, 3" 不同，因为第二个字符串中有空格。var b = [1, 2, 3] 与 b = [a, 2, 3] 不同，因为第二个数组中的第一个元素不同。试试下面的代码// First timevar a = [1, 2, 3];var b = [1, 2, 3];var c = "1,2,3";a == c;b == c;a == b;//Second timeconsole.log(a == c);console.log(b == c);console.log(a == b);a = [1, 2, 3];b = [1, 2, 3];c = "1,2,3";console.log(a == c);console.log(b == c);console.log(a == b);