• JavaScript Video Tutorials

JavaScript DataView setUint8() Method

Previous
Next

The JavaScript DataView setUint8() method stores an 8-bit unsigned integer (a byte) at the specified byte offset from the start of the DataView.

If the specified byteOffset is outside the bounds of the DataView, the method throws a 'RangeError' exception.

Syntax

Following is the syntax of the JavaScript DataView setUint8() method −

setUint8(byteOffset, value)

Parameters

This method accepts two parameters named 'byteOffset' and 'value', which are described below −

  • byteOffset − It is the position in the DataView where the byte will be stored.
  • value − An 8-bit unsigned integer value needs to be stored.

Return value

This method returns undefined, as it only stores the byte value.

Example 1

The following is the basic example of the JavaScript DataView setUnit8() method.

<html>
<body>
<script>
   //creating array buffer
   const buffer = new ArrayBuffer(8);
   const data_view = new DataView(buffer);
   const number = 20;
   const byteOffset = 0;
   document.write("Number value: ", number);
   document.write("<br>The byteOffset value: ", byteOffset);
   //using the setUnit8() method
   data_view.setUint8(byteOffset, number);
   document.write("<br>Store value: ", data_view.getUint8());
</script>
</body>
</html>

Output

The above program stores the number and displays it as −

Number value: 20
The byteOffset value: 0
Store value: 20

Example 2

The following is another example of the JavaScript DataView setUint8() method. We use this method to store the unsigned 8-bit integer value 50 at the specified byte offset position 2.

<html>
<body>
<script>
   //creating array buffer
   const buffer = new ArrayBuffer(8);
   const data_view = new DataView(buffer);
   const number = 50;
   const byteOffset = 2;
   document.write("Number value: ", number);
   document.write("<br>The byteOffset value: ", byteOffset);
   //using the setUnit8() method
   data_view.setUint8(byteOffset, number);
   document.write("<br>Store value: ", data_view.getUint8(2));
</script>
</body>
</html>

Output

Once the above program is executed, it stores the number 50 and displays it as −

Number value: 50
The byteOffset value: 2
Store value: 50

Example 3

If the byteOffset parameter value is outside the bound of the data view, it will throw a 'RangeError' exception.

<html>
<body>
<script>
   //creating an array buffer
   const buffer = new ArrayBuffer(8);
   const data_view = new DataView(buffer);
   const number = 200;
   const byteOffset = 9;
   document.write("Number value: ", number);
   document.write("<br>The byteOffset: ", byteOffset);
   try {
      //using the setUnit8() method
      data_view.setUint8(9, 200);
      document.write(dv.getUint8(0));
   } catch (error) {
      document.write("<br>", error);
   }
</script>
</body>
</html>

Output

After executing the above program, it throws a 'RangeError' exception.

Number value: 200
The byteOffset: 9
RangeError: Offset is outside the bounds of the DataView
Print Page
Previous
Next
Advertisements