在此代码中：
"here are things"返回值不应为str吗？我假设它将第一个值传递给累加器"here are things "。有没有办法返回using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using NetworksApi.TCP.CLIENT;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
Form1 client;
public Form1()
{
InitializeComponent();
}
private void textBox2_KeyDown(object sender, KeyEventArgs e)
{
}
private void button2_Click(object sender, EventArgs e)
{
if (textBox3.Text!= "" &&textBox4.Text!="")
{
client = new Form1();
client.ClientName = textBox4.Text;
client.ServerIp = textBox3.Text;
client.Connect();
}
else
{
MessageBox.Show("Fill it completely");
}
}
private void button3_Click(object sender, EventArgs e)
{
}
private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
System.Environment.Exit(System.Environment.ExitCode);
}
}
}
？
答案 0 :(得分：4)
我假设它将第一个值传递给累加器
正确，因为未定义初始值，集合的第一个元素将成为初始值。固定？提供初始值：
b = ['here', 'are', 'things']
b.inject('') { |memo, elem| memo + "#{elem} " } # => "here are things "
答案 1 :(得分：1)
在单词之前添加空格，就像这样。 结果中没有尾随空格。
["here", "are", "things"].inject { |str, v| str+=" #{v}" }
#=> "here are things"
你也可以做类似下面的事情但仍然没有尾随空格
['here', 'are', 'things'].inject { |m, e| "#{m} #{e}" }
#=> "here are things"