Two ways to keep alert from popping up

 
<script language=javascript> 
function window.alert(str){ 
//Here is empty
} 
alert("fffffff"); 
</script> 
 I'm going to reload it alert The function definitions function window.alert(str){} Put it in a public one js In the file   He didn't receive the alert The trouble of  

 If prompted, define it this way  
function window.alert(str){ 
//Open a mode dialog box here to show STR string closed after a delay of 20ms
}