JavaScript check if variable exists (is defined/initialized)

PHOTO

Thu Jun 24 2021 13:41:02 GMT+0000 (Coordinated Universal Time)

if (typeof variable !== 'undefined') {
    // the variable is defined
}

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https://stackoverflow.com/questions/5113374/javascript-check-if-variable-exists-is-defined-initialized

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JavaScript

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Get URL parameters Check if Number is Even/Odd JavaScript check if variable exists (is defined/initialized)

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JavaScript check if variable exists (is defined/initialized)

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