The first two only difference is that the loop and the order of the judgments are different, do-while than while more than one cycle, I do not give an example.
For loop I believe that we can not be ripe, we will see for-in this sentence.
This is actually for the array, JS array initialization is also very strange, such as we write in the script node: (also note the initialization of the array, with the brackets)
<script type= "Text/javascript" > <!--document.write ("test<br>"); var a=[3,4,5,7]; for (var test in a) {document.write (test+ ":" +a[test]+ "<br>"); }--> </script>
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For in instance two
<ptml> <body> <script type= "Text/javascript" > var x var mycars = new Array () mycars[0] = "BMW" Myca RS[1] = "Benz" mycars[2] = "Bentley" for (x in Mycars) {document.write (mycars[x] + "<br>")} </script> </b Ody> </ptml>
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Javascrpt for
<script type= "Text/javascript" > for (i = 0; I <= 5; i++) {document.write ("number is" + i) document.write ("<br& gt; ")} </script>
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The number is 0.
The number is 1.
The number is 2.
The number is 3.
The number is 4.
The number is 5.
Explain:
The step value for the For loop starts at i=0.
As long as I is less than or equal to 5, the loop will continue to run.
Loop every time, I will add 1.
Javascrpt Do While:
<ptml> <pead> <title> A JavaScript example that uses the Do...while loop </title> </pead> <body> < p> <script type= "Text/javascript" > i = 0 do {document.write (i + ' <br> ') i++} while (I <= 5) </script>
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The number is 0.
The number is 1.
The number is 2.
The number is 3.
The number is 4.
The number is 5.
Explain:
I equals 0.
The loop will run first.
Once per cycle, I will accumulate 1.
When I is less than or equal to 5 o'clock, the loop continues to run.
Javascrpt while
<script type= "Text/javascript" > i = 0 while (i <= 5) {document.write ("number is" + i) document.write ("<br> ") i++} </script>
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The number is 0.
The number is 1.
The number is 2.
The number is 3.
The number is 4.
The number is 5.
Explain:
I equals 0.
When I is less than or equal to 5 o'clock, the loop continues to run.
Every time the loop runs, I will accumulate 1.
JavaScript Sample Code Explanation: This JavaScript example uses the Do...while loop statement.
A loop statement allows you to repeat a line or lines of code, followed by a repeating code, while followed by a condition that terminates the loop. In this JavaScript example, set a variable to the I,i initial value of 0,i++ to add 1 to the value of I after each repetition, terminating the loop condition as while (I <= 5), that is, to terminate the loop once I has a value greater than 5. In this example, a repeating loop statement is a document.write statement inside a while loop. </p>
From the above example, we can see the difference between JS For,for in, while and do.
