如何在javascript中将双精度（64位）数转换/存储到32位浮点数或UInt16

Question

Assume I can bare the loss of digits/precision to some degree. I find that to send a 64bit (8 bytes) number over the network sometimes is overkilled. I want the data to use less bandwidth but maintain certain accuracy. But I don't know the correct way to store a number in 32 bit or 16 bit data in javascript.

Answer 1

Here's how you can convert a JavaScript number to an array buffer holding a 32 bit float or a 16 bit unsigned integer:

 let float64 = 3.141592653589793238462643383279502884197; let float32View = new DataView(new ArrayBuffer(4)); float32View.setFloat32(0, float64); let uint16View = new DataView(new ArrayBuffer(2)); uint16View.setUint16(0, float64); console.log(float64); console.log(float32View.getFloat32(0)); console.log(uint16View.getUint16(0));