JavaScript Operator: typeof
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In JavaScript,
the typeof operator returns
the type of a variable, object, function or expression, e.g.
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x
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typeof x
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false
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boolean
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true
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boolean
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0
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number
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1
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number
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"0"
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string
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"1"
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string
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NaN
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number
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Infinity
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[???]
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-Infinity
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[???]
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""
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string
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"10"
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string
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"ten"
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string
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[ ]
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object
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[10]
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object
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[5,10]
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object
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["ten"]
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object
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["five","ten"]
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object
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function(){}
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function
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{ }
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object
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null
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object
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undefined
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undefined
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The type of a date, array
or null is an object, which means that you cannot directly use the typeof operator to work out if a
JavaScript object is an array rather than a date, say.
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