var i=0; for (i=0;i...">

Using a string as loop expressions and conditions

The following loop works:

<html>
<body>
<script type="text/javascript">
var i=0;
for (i=0;i<=5;i++)
{
document.write("The number is " + i);
document.write("<br />");
}
</script>
</body>
</html>

But the following:

<html>
<body>
<script type="text/javascript">
var i=0;
var x="i=0;i<=5;i++"
for (x)
{
document.write("The number is " + i);
document.write("<br />");
}
</script>
</body>
</html>

I just wanted to create a simple variable. Please carry me as I am new to JavaScript and let me know what I am missing.

Let me provide a sample Google Gadget:

<?xml version="1.0" encoding="UTF-8" ?> 
<Module> 
<ModulePrefs title="Sample Gadget" /> 
<UserPref name="order" 
          display_name="Results Order" 
          default_value="i = 0; i <= 5; i++" datatype="enum"> 
<EnumValue value="i = 0; i <= 5; i++" display_value="Ascending"/> 
<EnumValue value="i = 5; i >= 0; i--" display_value="Descending"/> 
</UserPref> 
<Content type="html"><![CDATA[ 
<script type="text/javascript"> 
var i=0; 
for (__UP_order__) 
{ 
document.write("The number is " + i); 
document.write("<br />"); 
} 

</script> 
]]></Content> 
</Module>

This does not work because of the <> tags (they are not supported), and so I tried to define a variable for the value of EnumValue.

+3
source share
3 answers

When you say var x="i=0;i<=5;i++", you create a text string. This is not interpreted by JavaScript as you expect.

. , , , "hello" "sdflkjsdflkjsdflj". JavaScript , / . , , - ...

var i=0;
var start=0; //you can change the start position by changing this
var end=5;   //and you can change the end also

for (i=start;i<=end;i++)
{
document.write("The number is " + i);
document.write("<br />");
}
+5

: . "i=0;i<=5;i++" - ( , ). for , - , , . ( , - , ? , - . El Ronnoco's)

+4

Since x is a string, and you cannot use a string for an operator. If you need to change the upper bound of the for statement, you can use a variable instead of patch number 5.

0
source

Source: https://habr.com/ru/post/1788528/


All Articles