本文實例講述了JavaScript通過prototype給對象定義屬性的用法。分享給大家供大家參考。具體分析如下：
下面的JS代碼定義了movie對象。在使用對象的過程中又通過prototype給對象添加了isComedy屬性，調用的時候直接使用object.isComedy即可，非常方便。
<script type="text/javascript">
<!--
function movieToString() {
return("title: "+this.title+" director: "+this.director);
}
function movie(title, director) {
this.title = title;
this.director = director || "unknown"; //if null assign to "unknown"
this.toString = movieToString; //assign function to this method pointer
}
var officeSpace = new movie("OfficeSpace");
var narnia = new movie("Narnia","Andrew Adamson");
movie.prototype.isComedy = false; //add a field to the movie's prototype
document.write(narnia.toString());
document.write("<br />Narnia a comedy? "+narnia.isComedy);
officeSpace.isComedy = true; //override the default just for this object
document.write("<br />Office Space a comedy? "+officeSpace.isComedy);
//-->
</script>
希望本文所述對大家的javascript程序設計有所幫助。