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Javascript 反转if语句_Javascript_If Statement_Conditional Statements - Fatal编程技术网
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Javascript 反转if语句

javascript if-statement

Javascript 反转if语句,javascript,if-statement,conditional-statements,Javascript,If Statement,Conditional Statements,我理解if条件是如何工作的。像这样： if (condition) { block of code to be executed if the condition is true } 但是，如果语句正确，我如何反转，例如不要触发这行代码 if $("span:contains('399')) { block of code to be executed if the condition is false } javascript 101。。。如果条件{…} if (!cond

我理解if条件是如何工作的。像这样：

if (condition) {
    block of code to be executed if the condition is true
}
但是，如果语句正确，我如何反转，例如不要触发这行代码

if $("span:contains('399')) {
    block of code to be executed if the condition is false
}
javascript 101。。。如果条件{…} 
if (!condition) {
    block of code to be executed if the condition is false
}