JavaScript 中检查 Number 是否不大于 0
要检查数字是否不大于 0，请使用逻辑 NOT ! 运算符来否定条件，例如 !(num > 0)。 如果数字不大于 0，条件将返回 true，否则返回 false。
const num = -5;
if (!(num > 0)) {
console.log('✅ number is not greater than 0');
} else {
console.log('⛔️ number is greater than 0');
}
我们使用逻辑 NOT ! 运算符来否定大于号。
请注意，我们必须将条件括在括号中。 如果我们不这样做，我们就会使用逻辑 NOT (!) 运算符来否定 num 变量的值。
另一种更常见的方法是使用小于或等于符号。
要检查一个数字是否不大于 0，请检查该数字是否小于或等于 0，例如 num <= 0。如果条件返回 true，则数字不大于 0。
const num = -5;
if (num <= 0) {
console.log('✅ number is not greater than 0');
} else {
console.log('⛔️ number is greater than 0');
}
此代码片段实现了相同的结果。 但是，它更直观，更常用。
如果数字小于或等于 0，那么我们知道它不大于 0。
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