javascript - When we store a method in a variable and then call it, Why does the context object change to the global window object? -

-

नीचे उदाहरण jqfundamentals से लिया गया है, 

  var person = {firstName: 'Boaz' , अंतिमनाम: 'प्रेषक', नमस्कार: कार्य () {लॉग ('हाय,' + this.firstName); }}; Var sayIt = person.greet; // एक चर में विधि को स्टोर करें यह (); // logs 'हाय, अपरिभाषित' - उह-ओह   
 स्पष्टीकरण के रूप में,  
 जब हम एक चर में ग्रिट () विधि को संग्रहीत करते हैं तो इसे कहते हैं और फिर कॉल करें SayIt (), संदर्भ वस्तु वैश्विक विंडो ऑब्जेक्ट में बदल जाती है, व्यक्ति ऑब्जेक्ट नहीं। चूंकि खिड़की ऑब्जेक्ट में कोई प्रॉपर्टी नहीं है, इसलिए जब हम इसे एक्सेस करने का प्रयास करते हैं तो हम अनिर्धारित होते हैं।  
 मेरी समस्या है  
 जब हम एक वेरिएबल में ग्रिड () विधि को संचित करते हैं तो इसे कहते हैं और फिर कहते हैं यह () क्यों संदर्भ वस्तु वैश्विक विंडो ऑब्जेक्ट में बदलती है?   
 
 
 यह युक्ति है,    
 P> निम्न चरणों का पालन किया जाता है जब फ़ंक्शन ऑब्जेक्ट F में निहित फ़ंक्शन कोड के लिए निष्पादन संदर्भ में प्रवेश करता है, एक कॉलर यह प्रदान किया गया, और एक कॉलर प्रदान की गई तर्क:  
     
  1.  यदि फ़ंक्शन कोड  thisArg   thisArg  पर सेट करें।  
  2.  यदि  thisArg   null  या  अपरिभाषित ,     
          
     > इसलिए जब  सख्त मोड ,  यह  में  अपरिभाषित  संदर्भित होगा, अन्यथा यह वैश्विक ऑब्जेक्ट को संदर्भित करेगा।

Comments

Post a Comment

Popular posts from this blog

Pygame memory leak with transform.flip -

-
Today I came across an interesting issue which, by writing a small side scroller, instead of a sprite sheet, I was planning to use because I lacked a good "packer" for making phantom sheets (and honestly with patience and passion as it is only a test project). Anyway, I showed the animation running on the right of 8 PNG (with transparency). I considered it a good idea to prepare the flipped images to run on the left in the consultant, and the frame is not framed when the game is running (Flip actually consumes a lot of CPU like I Was measured). > To get access to the loop, I get the memory leak self.move_l = [# 8 PNG images with transparency to the right] For the self in IMG. Move_l: self.move_r.append (pygame.transform.flip (img, true, false) error traceback: traceback (most recent Call final): The file "D: \ Python 34 \ _Projects \ efg \ efg.py", in line 196, in the & lt; module & gt; main = master program ((1024, 680)) "D: \ Python ...
Read more

python - Writing Greek in matplotlib labels, titles -

-
Image
I'm trying to write some text for labels, shape titles etc. with my plots, but no benefit till now Has not happened . I do not want to print specific characters (I know how to use special characters), I want to write the entire text in Greek (maybe Unicode and text ' ?). , suggesting that I would like to mention that for some reason I can not get matplotlib to cooperate with Tex (using IPython notebook from Anaconda in Ubuntu 14.10) so that there really is an option Will not be the first. I tried loading the Arial font and it loads successfully but again I get square blocks instead of characters. I import matplotlib.font_manager FM PROP = FM Font Properties (fname = '/ usr / share / fonts / truetype / msttcorefonts / Arial.ttf') And then to display the string I u'Î? ? I ?? Î¿Ï ?? ÎμÎ »second ?? μΠ± i ?? I ± i ?? I ?? Used ο किया? ? Î¿Î¼Î¿Î¯Ï ?? I ?? I · I ?? ' . Ariel is considered to be fully presented to Greek and I have used it many times ...
Read more

c# - Call function from DLL -

-
It is well known that you can work in a DLL, referencing DLL and then your main performance Can call functional function I want to know that the reverse route is also possible? So I want to call a function in the main executable from DLL, without actual function which should be called without DLL. Reason: I'm working on a plugins system. Yes, executables can be added as references in your project, you can use them in the same way On which you call functions from referenced DLS
Read more