Js--do while, for loop statements

Do and loop structure

do{

Circulation body;

}while (cyclic conditions);

Show "Hello World" five times

var I=1;

while (I<5)

{

Alert ("Hello World")

i++;

}

var j=6;

do{

Alert ("Hello World")

j + +;

}while (j<=5);

The loop body is executed at least once, and the while loop may not execute at one time

Ask for factorial of 5, 5! =5*4*3*2*1

War jiecheng=1,num=5;

do{

Jiecheng=jiecheng*num;

num--;

}while (num>=1);

Alert ("jiecheng=" +jiecheng);

For loop

for (expression 1 loop variable initialization statement; expression 2 loop condition; expression 3 change loop variable statement)

{

Circulation body;

}

Ask for factorial, 5!

var jiecheng=1;

for (num=5;num>=1;num--)

{

Jiecheng=jiecheng*num;

}

Alert ("jiecheng=" +jiecheng);

Omitting an expression

for (Var i=1;i<=5;i++)

{

Alert ("Hello World");

}

Omit expression One

var I=1;

for (; i<=5;i++)

{

Alert ("Hello World");

}

Ellipsis expression two--dead loop

Omit expression Three

for (i=1;i<=5;)

{

Alert ("Hello World");

i++;

}

Nested loops

Print ********** on the page

for (Var i=1;i<=10;i++)

{

document.write ("*");

}

Print five lines of 10 stars

for (Var j=1;j<=5;j++)

{

for (Var i=1;i<=10;i++)

document.write ("*");

document.write ("<br/>");

}

The number of stars per row is the same as the number of rows

for (Var i=1;i<=5;i++)

{

for (Var j=1;j<=i;j++)

{

document.write ("*");

}

document.write ("<br/>");

}

Js--do while, for Loop statement