// call this inside your component
useEffect(() => {
console.log(myInputValue);
}, [myInputValue]) // this dependency array listens for these prop/state value changes and runs the code in the block above whenever those values update.
This generally occurs due to React's lifecycle stages for components. If you add a console.log inside your render method then anything that would cause your component to re-render - which is complete normal from prop or state changes - will trigger the console log to occur.
You can make use of React's useEffect as follows to make sure your console log only logs when a specific value changes like this:
// call this inside your component
useEffect(() => {
console.log(myInputValue);
}, [myInputValue]) // this dependency array listens for these prop/state value changes and runs the code in the block above whenever those values update.
This is problably due to React's Strict Mode. This mode invokes many methods, like the function component body, twice in order to spot side-effects that make your components not idempotent. If this is why you see the output twice, you can:
Disable Strict Mode by removing the <StrictMode> tag. In next.js, set reactStrictMode to false in the next.config.js file, or
Install React Developer Tools extension, which will take care of printing the duplicated log in a lighter gray color.
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这通常是由于React的生命周期阶段而发生的。如果您在渲染方法中添加
console.log，那么任何会导致您的组件重新渲染的任何东西 - 从prop或状态>状态>状态更改 - 将触发控制台日志发生。您可以使用React的
使用，如下所示，以确保在类似的特定值更改时仅在log时log log：This generally occurs due to React's lifecycle stages for components. If you add a
console.loginside your render method then anything that would cause your component to re-render - which is complete normal fromproporstatechanges - will trigger the console log to occur.You can make use of React's
useEffectas follows to make sure your console log only logs when a specific value changes like this:这很有可能是由于React的严格模式 。此模式调用了许多方法，例如功能组件主体，两次，以发现使组件不同意的副作用。如果这就是为什么看到输出两次的原因，则可以：
＆lt; strictmode＆gt;标签来禁用严格模式。在next.js中，将reactrictMode设置为next.config.js文件中的false，或This is problably due to React's Strict Mode. This mode invokes many methods, like the function component body, twice in order to spot side-effects that make your components not idempotent. If this is why you see the output twice, you can:
<StrictMode>tag. In next.js, setreactStrictModeto false in thenext.config.jsfile, or