使用 StringBuilder 追加 [英] Appending with StringBuilder

问题描述

我有 5 个复选框，我必须选择多个复选框.

I have 5 checkboxes and I have to select multiple checkboxes.

我做了一个这样的代码来检查复选框是否被选中:

I made a code like this to check check box is checked:

sports=(CheckBox)findViewById(R.id.sports_btn);
sports.setOnClickListener(new OnClickListener() {

    @Override
    public void onClick(View v) {
        if (sports.isChecked() == true)
        list.add("4");
    }
}); 

我正在向数组列表中添加一个值:

I am adding a value to an array list:

list ArrayList<String> list = new ArrayList<String>();

我正在以字符串形式检索值，如下所示:

and I am retrieving the value as string like this:

StringBuilder sb = new StringBuilder();
for(int  i =0; i < list.size(); i++)
{
    for (String str: list)
    {  
        sb.append(str.toString());
        sb.append(",");
    }

}
String sel_cat = sb;

我正在获取字符串，但如果选择了两个值，它将像 2,3，如何删除最后一个逗号?我不希望字符串的最后一个逗号必须像 2,3.

I am getting the string but if two values are selected it is coming like 2,3, How to remove that last comma? I don't want the last comma the string has to be like 2,3.

推荐答案

StringBuilder sb = new StringBuilder();
sb.deleteCharAt(sb.length()-1) 

或者在您的代码中，使用

StringBuilder sb = new StringBuilder();

for(int  i =0;i<list.size();i++)
{
    String prefix = "";
    for (String str : list)
    { 
        sb.append(prefix);
        prefix = ",";
        sb.append(str);  
    }
}

String sel_cat = sb;

这篇关于使用 StringBuilder 追加的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！