JavaScript DataView.getInt32()用法及代码示例

JavaScript DataView.getInt32() 是 dataView 中的内置方法。它用于在指定位置获取有符号的 32 位整数(长)数。

注意：有符号整数值的 32 位整数值的范围是从 2,147,483,648 到 2,147,483,647。

用法

dataview.getInt32(byteOffset)

参数

byteoffset: 从读取数据的视图开始的偏移量，以字节为单位。

返回值

此方法返回一个带符号的 32 位整数。

浏览器支持

Chrome	9
Safari	5.1
Firefox	15
Opera	12.1

例子1

<script>
//JavaScript to illustrate dataview.getInt32() method
// creating a ArrayBuffer 
var JavaTpoint = new ArrayBuffer(8);
// creating a view
var arr = new DataView(JavaTpoint);
// put the value 23.3 at slot 1
document.write("If we give a float value, the output will be an Integer<br><br>");
arr.setInt32(1,23.3);
document.write(arr.getInt32(1));
//expected output:23
</script>

输出：

If we give a float value, the output will be an Integer
23

例子2

<script>
//JavaScript to illustrate dataview.getInt32() method
// if there is no data to be stored then it returns Nan
// creating a ArrayBuffer 
var JavaTpoint = new ArrayBuffer(10);
// creating a view
var arr = new DataView(JavaTpoint);
// NO Data
arr.getInt32(1);
document.write("If there is no data to be stored, Output will Be:<br>")
document.write(arr.getInt32(1));
//expected output:0
</script>

输出：

If there is no data to be stored, Output will Be:
0

例子3

<script>
//JavaScript to illustrate dataview.getInt32() method
// creating a ArrayBuffer 
var JavaTpoint = new ArrayBuffer(8);
// creating a view
var arr = new DataView(JavaTpoint);
//We can also use math function like Math.PI
document.write("Convert the PI value 3.14 to 3<br><br>");
arr.setInt32(1,Math.PI);
document.write(arr.getInt32(1));
//expected output:3
</script>

输出：

Convert the PI value 3.14 to 3

3

示例 4

<script>
//JavaScript to illustrate dataview.getInt32() method
// creating a ArrayBuffer 
var JavaTpoint = new ArrayBuffer(8);
// creating a view
var arr = new DataView(JavaTpoint);
// put the value 7 at slot 1
arr.setInt32(1,7);
document.write("If we give an Integer value, Output will  be Integer<br><br>");
document.write(arr.getInt32(1));
//expected output:7
</script>

输出：

If we give an Integer value, Output will be Integer

7

相关用法

注：本文由纯净天空筛选整理自 JavaScript DataView.getInt32() method。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。