1. Create a script block
1: <script language = "JavaScript">
2: JavaScript code goes here
3: </script>
2. Hide the script code
1: <script language = "JavaScript">
2: <! --
3: document. write ("Hello ");
4: // -->
5: </script>
Related code will not be executed in browsers that do not support JavaScript.
3 display when the browser does not support
1: <noscript>
2: Hello to the non-JavaScript browser.
3: </noscript>
4. Link an external script file
1: <script language = "JavaScript" src = "/" filename. js "> </script>
5. Comment the script
1: // This is a comment
2: document. write ("Hello"); // This is a comment
3 :/*
4: All of this
5: is a comment
6 :*/
6. output to the browser
1: document. write ("<strong> Hello </strong> ");
7. Define Variables
1: var myVariable = "some value ";
8 string Addition
1: var myString = "String1" + "String2 ";
9 string SEARCH
1: <script language = "JavaScript">
2: <! --
3: var myVariable = "Hello there ";
4: var therePlace = myVariable. search ("there ");
5: document. write (therePlace );
6: // -->
7: </script>
10 string replacement
1: thisVar. replace ("Monday", "Friday ");
11 format a string
1: <script language = "JavaScript">
2: <! --
3: var myVariable = "Hello there ";
4: document. write (myVariable. big () + "<br> ");
5: document. write (myVariable. blink () + "<br> ");
6: document. write (myVariable. bold () + "<br> ");
7: document. write (myVariable. fixed () + "<br> ");
8: document. write (myVariable. fontcolor ("red") + "<br> ");
9: document. write (myVariable. fontsize ("18pt") + "<br> ");
10: document. write (myVariable. italics () + "<br> ");
11: document. write (myVariable. small () + "<br> ");
12: document. write (myVariable. strike () + "<br> ");
13: document. write (myVariable. sub () + "<br> ");
14: document. write (myVariable. sup () + "<br> ");
15: document. write (myVariable. toLowerCase () + "<br> ");
16: document. write (myVariable. toUpperCase () + "<br> ");
17:
18: var firstString = "My String ";
19: var finalString = firstString. bold (). toLowerCase (). fontcolor ("red ");
20: // -->
21: </script>
12. Create an array
1: <script language = "JavaScript">
2: <! --
3: var myArray = new Array (5 );
4: myArray [0] = "First Entry ";
5: myArray [1] = "Second Entry ";
6: myArray [2] = "Third Entry ";
7: myArray [3] = "Fourth Entry ";
8: myArray [4] = "th Entry ";
9: var anotherArray = new Array ("First Entry", "Second Entry", "Third Entry", "Fourth Entry", "th Entry ");
10: // -->
11: </script>
13. Sort Arrays
1: <script language = "JavaScript">
2: <! --
3: var myArray = new Array (5 );
4: myArray [0] = "z ";
5: myArray [1] = "c ";
6: myArray [2] = "d ";
7: myArray [3] = "";
8: myArray [4] = "q ";
9: document. write (myArray. sort ());
10: // -->
11: </script>
14. Split string
1: <script language = "JavaScript">
2: <! --
3: var myVariable = "a, B, c, d ";
4: var stringArray = myVariable. split (",");
5: document. write (stringArray [0]);
6: document. write (stringArray [1]);
7: document. write (stringArray [2]);
8: document. write (stringArray [3]);
9: // -->
10: </script>
15. A warning message is displayed.
1: <script language = "JavaScript">
2: <! --
3: window. alert ("Hello ");
4: // -->
5: </script>
16 pop-up confirmation box
1: <script language = "JavaScript">
2: <! --
3: var result = window. confirm ("Click OK to continue ");
4: // -->
5: </script>
17 define functions
1: <script language = "JavaScript">
2: <! --
3: function multiple (number1, number2 ){
4: var result = number1 * number2;
5: return result;
6 :}
7: // -->
8: </script>
18. Call JS Functions
1: <a href = "#" onClick = "functionName ()"> Link text </a>
2: <a href = "/" javascript: functionName "()"> Link text </a>
19. Execute the function after the page is loaded.
1: <body onLoad = "functionName ();">
2: Body of the page
3: </body>
20 condition judgment
1: <script>
2: <! --
3: var userChoice = window. confirm ("Choose OK or Cancel ");
4: var result = (userChoice = true )? "OK": "Cancel ";
5: document. write (result );
6: // -->
7: </script>
21 specified number of cycles
1: <script>
2: <! --
3: var myArray = new Array (3 );
4: myArray [0] = "Item 0 ";
5: myArray [1] = "Item 1 ";
6: myArray [2] = "Item 2 ";
7: for (I = 0; I <myArray. length; I ++ ){
8: document. write (myArray [I] + "<br> ");
9 :}
10: // -->
11: </script>
22. set future execution
1: <script>
2: <! --
3: function hello (){
4: window. alert ("Hello ");
5 :}
6: window. setTimeout ("hello ()", 5000 );
7: // -->
8: </script>
23. Scheduled function execution
1: <script>
2: <! --
3: function hello (){
4: window. alert ("Hello ");
5: window. setTimeout ("hello ()", 5000 );
6 :}
7: window. setTimeout ("hello ()", 5000 );
8: // -->
9: </script>
24 cancel scheduled execution
1: <script>
2: <! --
3: function hello (){
4: window. alert ("Hello ");
5 :}
6: var myTimeout = window. setTimeout ("hello ()", 5000 );
7: window. clearTimeout (myTimeout );
8: // -->
9: </script>
25. Execute the function when uninstalling the page.
1: <body onUnload = "functionName ();">
2: Body of the page
3: </body>