1. Internal introduced manner:
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script type attribute defaults to "text / javascript", you can not write
. 1 < Script type = "text / JavaScript" > 2 function the init () { . 3 // // Case II: writing the display image rotation operation timing (three seconds) . 4 // the window.setInterval ( "changeImg ()", 3000); // window can be omitted . 5 . 6 @ case 3: 1 ad image display timing setting operation. 7 // here not add var: var plus local variable, global variable without var . 8 Time = the setInterval ( " showAd () " , 3000 ); . 9 } 10 . 11 // writing function 12 is var I= 0 ; 13 is function changeImg () { 14 I ++ ; 15 // get image position and sets the src attribute value 16 document.getElementById ( " IMG1 " ) .src = " ../img/ " + I + " .jpg " ; . 17 IF (I == 2 ) { 18 is I = 0 ; . 19 } 20 is } 21 is 22 is //2. The function of writing display ad image 23 is function showAd () { 24 // 3. Ad image acquisition position 25 var AdeLE, an Austrian = document.getElementById ( " IMG2 " ); 26 is // 4. modify elements inside attribute allowed to display 27 adEle.style.display = " Block " ; 28 // 5. the operation timing of clear image display 29 the clearInterval (Time); 30 // 6. the timing of the operation is provided hidden image 31 is Time = the setInterval ( " hiddenAd () " , 3000 ); 32 33 is } 34 // function written hide 7. 35 function hiddenAd () { 36 // 8. The acquired image position and sets the value of the style attribute display none 37 [ document.getElementById ( " IMG2 " ) .style.display = " none " ; 38 is // 9. the timing of the operation to clear the hide 39 the clearInterval (Time); 40 } 41 is 42 is </ Script >
2. External introduced:
- Js create a file, writing Javascript code in it, in the html file using the script src attribute tag introduced into the external file js
<script type="text/javascript" src="1.js"></script>
1.js file:
. 1 function the init () { 2 // // Case II: writing the display image rotation operation timing (three seconds) . 3 // the window.setInterval ( "changeImg ()", 3000); // can be omitted window 4 5 // . case 3: 1 to set the display operation timing of image ads 6 // here not add var: var plus local variable, global variable without var . 7 Time = the setInterval ( "showAd ()", 3000 ); . 8 } . 9 10 // Write function . 11 var I = 0 ; 12 is 13 is function changeImg () { 14 I ++ ; 15 // get image position and sets the src attribute value 16 . document.getElementById ( "IMG1") the src = "../img/" I + + ".jpg" ; . 17 IF (I == 2 ) { 18 is I = 0 ; . 19 } 20 is } 21 is 22 is // 2. ad image writing display function 23 is function showAd () { 24 // 3. ad image acquisition position 25 var AdeLE, an Austrian = document.getElementById ( "IMG2" ); 26 is // 4. modify elements inside attribute allowed to display 27 AdeLE, an Austrian. =. style.display "Block" ; 28 // 5. the operation timing of clear image display 29 the clearInterval (Time); 30 //6. Set the hide operation timing 31 is Time = the setInterval ( "hiddenAd ()", 3000 ); 32 33 is } 34 is // function written hide 7. 35 function hiddenAd () { 36 // 8. The image acquiring position and set the display style attribute is none 37 [ document.getElementById ( "IMG2"). style.display = "none." ; 38 is // 9. the timing of the operation to clear the hide 39 the clearInterval (Time); 40 }