angularjs - How to check webpage is available or not using javascript -

-

i want make web page request if web page available. have written app using angularjs + javascript. there way determine whether webpage available or not using javascript ?

if page in question on different origin, can't without using server somewhere or relying on other page implementing cross-origin resource sharing , supporting origin, because of same origin policy.

if page in question on same origin, can ajax call query it:

var xhr = new xmlhttprequest(); xhr.open("head", url); xhr.onreadystatechange = function() {     if (xhr.readystate == 4) {         if (xhr.status == 200) {             // worked         } else {             // didn't         }     } }; xhr.send();

Comments

Post a Comment

Popular posts from this blog

c - Bitwise operation with (signed) enum value -

-
i using enumerator values flags: typedef enum { = 0x00, b = 0x01u, // u has no influence, expected c = 0x02u, // u has no influence, expected ... } enum_name; volatile unsigned char* reg = someaddress; *reg |= b; according misra-c:2004 bitwise operations shall not done signed type. unfortunately, compiler iar use signed int (or short or char) underlying type of enums, , option can find relates size, not signedness ("--enum-is-int"). according iar c/c++ development guide arm , pages 169 , 211, can define type of enum s if enable iar language extensions ( -e command-line option, or project > options > c/c++ compiler > language > allow iar extensions in ide). in particular, should define "sentinel" value, make sure compiler chooses correct type. prefers signed types, , uses smallest possible integer type, sentinel should largest positive integer corresponding unsigned integer type can describe. example, typedef enum
Read more

xslt - Unnest parent nodes by child node -

-
in xml there items 0-n attributes , item should copied each attribute new item 1 attribute. given xml this: <?xml version="1.0" encoding="utf-8" ?> <items> <item> <name>a</name> <attributes> <attribute> <key>attribute1</key> <value>1</value> </attribute> </attributes> </item> <item> <name>b</name> </item> <item> <name>c</name> <attributes> <attribute> <key>attribute1</key> <value>5</value> </attribute> <attribute> <key>attribute2</key> <value>2</value> </attribute> <attribute> <key>attri
Read more

YouTubePlayerFragment cannot be cast to android.support.v4.app.Fragment -

-
im stuck on 3 days , have tried have come across after lots of searching ,this post last resort, im trying open youtubeplayerfragment using navigation drawer youtubeplayerfragment cannot cast android.support.v4.app.fragment problem edit question : have updated code have used youtubeplayersupportfragment instead of youtubeplayerfragment ,i error in displayview method (case 4: fragment = new youtube(); break;) in main activity saying cannot convert youtube fragment , cannot logcat since cant run it edit question 2: code updated again have runtime problem ,heres logcat 07-22 22:15:09.782: e/androidruntime(20603): fatal exception: main 07-22 22:15:09.782: e/androidruntime(20603): process: net.frankandwalters, pid: 20603 07-22 22:15:09.782: e/androidruntime(20603): java.lang.nullpointerexception: attempt invoke virtual method 'void com.google.android.youtube.player.youtubeplayerview.a()' on null object reference 07-22 22:15:09.782: e/androidruntime(20603): @ com.goog
Read more