我尝试了以下方法:
if (oldValue && (oldValue <= 999))
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但如果数字为 0,这似乎不起作用。是否有正确的 Javascript 方法来执行此检查?
if(oldvalue > 0 && oldvalue < 998){} //if you don't want to include 0 or 998
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和
if(oldvalue >= 0 && oldvalue <= 998){} //if you do want to include 0 and 998
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