学用 ASP.Net 之 "字符串" (6): StringInfo 类

学完这个类没感到它会有什么用处, 同样的操作都不如在 string 类里方便, 还要 using System.Globalization;

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主要成员:

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/* 静态方法 */
StringInfo.GetNextTextElement();       //获取指定元素, 默认是获取第一个元素
StringInfo.GetTextElementEnumerator(); //获取枚举器
StringInfo.ParseCombiningCharacters(); //获取由序号组成的 int[]

/* 属性 */
LengthInTextElements; //元素数; 只读
String;               //对象拥有的字符串; 可读写

/* 对象方法 */
SubstringByTextElements(); //截取字符串

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构造函数及属性:

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protected void Button1_Click(object sender, EventArgs e)
{
    StringInfo sf = new StringInfo("abcdefg");
    int n1 = sf.LengthInTextElements; //7
    string s1 = sf.String;            //abcdefg

    TextBox1.Text = string.Concat(n1, "\n", s1);
}

protected void Button2_Click(object sender, EventArgs e)
{
    StringInfo sf = new StringInfo();
    int n1 = sf.LengthInTextElements; //0
    string s1 = sf.String;            //

    sf.String = "abc";
    int n2 = sf.LengthInTextElements; //3
    string s2 = sf.String;            //abc

    TextBox1.Text = string.Concat(n1, "\n", s1, "\n" + n2, "\n", s2);
}

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SubstringByTextElements() 方法:

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protected void Button1_Click(object sender, EventArgs e)
{
    StringInfo sf = new StringInfo("ABCDEFG");
    string s1 = sf.SubstringByTextElements(2);    //CDEFG
    string s2 = sf.SubstringByTextElements(2, 3); //CDE

    TextBox1.Text = s1 + "\n" + s2;
}

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三个静态方法:

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//StringInfo.GetNextTextElement()
protected void Button1_Click(object sender, EventArgs e)
{
    string s1 = StringInfo.GetNextTextElement("ABCDEFG");    //A
    string s2 = StringInfo.GetNextTextElement("ABCDEFG", 1); //B

    TextBox1.Text = s1 + "\n" + s2;
}

//StringInfo.ParseCombiningCharacters()
protected void Button2_Click(object sender, EventArgs e)
{
    int[] nArr = StringInfo.ParseCombiningCharacters("Asp.Net");

    TextBox1.Text = string.Join(", ", nArr); //0, 1, 2, 3, 4, 5, 6
}

//StringInfo.GetTextElementEnumerator(); 使用 IEnumerator 需 using System.Collections;
protected void Button3_Click(object sender, EventArgs e)
{
    string str = "ABCDEFG";
    string s1, s2;
    s1 = s2 = "";

    IEnumerator e1 = StringInfo.GetTextElementEnumerator(str);
    while (e1.MoveNext())
    {
        s1 += string.Format("{0} ", e1.Current); //A B C D E F G 
    }

    IEnumerator e2 = StringInfo.GetTextElementEnumerator(str, 2);
    while (e2.MoveNext())
    {
        s2 += string.Format("{0} ", e2.Current); //C D E F G
    }

    TextBox1.Text = s1 + "\n" + s2;
}

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