if ( document.getElementById("selector") != null ) { console.log("exist!"); } if ( $("selector")[0] ) { console.log("exist!"); } if ( $("selector").get(0) ) { console.log("exist!"); } if ( $("selector").length ) { console.log("exist!"); } if ( $("selector").size() ) { console.log("exist!"); } if ( $("selector").is('*') ) { console.log("exist!"); }
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