02-JS flow control statements

 

The if statement

if (condition) { 

statements executed during the establishment of the conditions; 

} {statement executed when the condition is not satisfied;} else

 

prompt [prɑːmpt]

prompt ( "content of the dialog prompt"); 

// such as: var age = prompt ( "content of the dialog prompt"); the contents so that the user input is equal to age.

 

alert [əˈlɜːrt]

alert ( "warning dialog content");

 

length [leŋθ]

abc.length, get the length of the string abc, the return value is the number

 

 new Date().getDay()

A few, the value returned is acquiring the week number (0-6).

 

switch statement

switch (function) { 

Case Value 1: When the function is equal to a value of 1, the statement is executed; 

BREAK; 

Case 2 values: when the function value is equal to 2, the statement is executed; 

BREAK; 

... 

default: When the above functions are not equal when the value of the statement is executed; 

}

 

document.write()

document.write ( "Content"); output "content" to the browser.

 

for loop

for ( < initial condition > ; < loop condition > ; < end loop > ) {
 < intermediate loop > ; 
} 
// do first initial condition 1 
// 2 loop condition is satisfied is determined 
@ 3 into the intermediate cycle if the establishment of body, if established directly out 
// intermediate 4 after executing the loop, the loop is then performed at the end of 
the 5 // End executed at the end loop, then perform 2

 

while loop

while (loop condition) { 
// if the loop proceeds to the loop condition is satisfied, otherwise skip 
< loop > 

}

 

do while loop

{do 
// loop proceeds directly, without determining 
< loop > 
} the while (loop condition); // if the loop condition is satisfied, then re-enters the loop

 

Note: If you know the fixed number of times with for ; if you must perform once the while with do ; otherwise use the while .

 

break与continue

We encounter a break in the cycle, directly out of the loop. 

Encounters continue in the cycle, the end of the cycle (the latter statement is not executed), the next cycle resumes.

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Origin www.cnblogs.com/mingliangge/p/12207660.html