golang bytes.buffer

 

 

 

 

 

 

 

 

 

 

 

    var buffer1 bytes.Buffer
    contents := "Simple byte buffer for marshaling data."
    fmt.Printf("Write contents %q ...\n", contents)
    buffer1.WriteString(contents)
    fmt.Printf("The length of buffer: %d\n", buffer1.Len())
    fmt.Printf("The capacity of buffer: %d\n", buffer1.Cap())
    fmt.Println()

Write contents "Simple byte buffer for marshaling data." ...  //打印結果是這樣的
The length of buffer: 39 //這裏輸出了總長度 是可用長度 也就是未讀取的長度
The capacity of buffer: 64 //容量長度

1     // 示例2。
2     p1 := make([]byte, 7)
3     n, _ := buffer1.Read(p1)
4     fmt.Printf("%d bytes were read. (call Read)\n", n)
5     fmt.Printf("The length of buffer: %d\n", buffer1.Len())
6     fmt.Printf("The capacity of buffer: %d\n", buffer1.Cap())
7     fmt.Println(string(p1))

下面是輸出內容 咱們從緩衝區讀取了7個字節到p1字節切片裏 那麼buffer1的屬性off(計數器)會向後挪移7個字節 長度也會減去7個字節 咱們看下輸出結果

7 bytes were read. (call Read)
The length of buffer: 32
The capacity of buffer: 64

再看下截取是示例：

buffer1.Truncate(6) //截取6個字節長度 從計數器爲起始位置