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Posted By

rolandog on 01/17/07


Tagged

object type array of typeof identification null undefined boolean


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type.of() - a more specific typeof()

Published in: JavaScript 

URL: http://rolandog.com/archives/2007/01/18/typeof-a-more-specific-typeof/

Helps identify correctly the type of whatever you put as an argument. This was adapted from http://www.planetpdf.com/developer/article.asp?ContentID=testingforobjecttypesin_ja

Embed | Plain TextExpand 
  1. var is={
  2. 	Null:function(a){
  3. 		return a===null;
  4. 	},
  5. 	Undefined:function(a){
  6. 		return a===undefined;
  7. 	},
  8. 	nt:function(a){
  9. 		return(a===null||a===undefined);
  10. 	},
  11. 	Function:function(a){
  12. 		return(typeof(a)==='function')?a.constructor.toString().match(/Function/)!==null:false;
  13. 	},
  14. 	String:function(a){
  15. 		return(typeof(a)==='string')?true:(typeof(a)==='object')?a.constructor.toString().match(/string/i)!==null:false;
  16. 	},
  17. 	Array:function(a){
  18. 		return(typeof(a)==='object')?a.constructor.toString().match(/array/i)!==null||a.length!==undefined:false;
  19. 	},
  20. 	Boolean:function(a){
  21. 		return(typeof(a)==='boolean')?true:(typeof(a)==='object')?a.constructor.toString().match(/boolean/i)!==null:false;
  22. 	},
  23. 	Date:function(a){
  24. 		return(typeof(a)==='date')?true:(typeof(a)==='object')?a.constructor.toString().match(/date/i)!==null:false;
  25. 	},
  26. 	HTML:function(a){
  27. 		return(typeof(a)==='object')?a.constructor.toString().match(/html/i)!==null:false;
  28. 	},
  29. 	Number:function(a){
  30. 		return(typeof(a)==='number')?true:(typeof(a)==='object')?a.constructor.toString().match(/Number/)!==null:false;
  31. 	},
  32. 	Object:function(a){
  33. 		return(typeof(a)==='object')?a.constructor.toString().match(/object/i)!==null:false;
  34. 	},
  35. 	RegExp:function(a){
  36. 		return(typeof(a)==='function')?a.constructor.toString().match(/regexp/i)!==null:false;
  37. 	}
  38. };
  39.  
  40. var type={
  41. 	of:function(a){
  42. 		for(var i in is){
  43. 			if(is[i](a)){
  44. 				return i.toLowerCase();
  45. 			}
  46. 		}
  47. 	}
  48. };

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