【www.gdgbn.com--php常用代码】

/* 常数字段 */
maxvalue //65535
minvalue //0

/* 静态方法 */
char.convertfromutf32()   //转 unicode 值到字符串
char.converttoutf32()     //转到 unicode 值
char.equals()             //=
char.getnumericvalue()    //数字字符转换成相应的值, 返回类型是 double
char.getunicodecategory() //获取字符类别
char.iscontrol()          //?控制字符
char.isdigit()            //?十进制数字(0..9)
char.ishighsurrogate()    //?高代理项码位(u+d800...u+dbff)
char.isletter()           //?字母
char.isletterordigit()    //?字母或十进制数字?
char.islower()            //?小写字母(a..z 等)
char.islowsurrogate()     //?高代理项码位(u+dc00...u+dfff)
char.isnumber()           //?数字(0..9 等)
char.ispunctuation()      //?标点符号?
char.isseparator()        //?分隔符(空格等)
char.issurrogate()        //?代理项码位
char.issurrogatepair()    //判断两个 char 对象是否形成代理项对
char.issymbol()           //?符号($ + = < > ^ ` | 等)
char.isupper()            //?大写字母(a..z 等)
char.iswhitespace()       //?空白
char.parse()              //转换单字符的 string 到 char
char.tolower()            //转小写
char.tolowerinvariant()   //转小写, 使用区域性规则
char.tostring()           //
char.toupper()            //转大写
char.toupperinvariant()   //转大写, 使用区域性规则
char.tryparse()           //尝试转换单字符的 string 到 char

/* 对象方法 */

compareto() //对比, 返回表示距离的整数

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getnumericvalue():
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protected void button1_click(object sender, eventargs e)
{
    double f1 = char.getnumericvalue("9");       // 9
    double f2 = char.getnumericvalue("a");       //-1
    double f3 = char.getnumericvalue("万");      //-1

    double f4 = char.getnumericvalue("a1b2", 3); // 2

    textbox1.text = string.concat(f1, "n", f2, "n", f3, "n", f4);
}

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convertfromutf32()、converttoutf32():
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protected void button1_click(object sender, eventargs e)
{
    string s1 = char.convertfromutf32(65);     //a
    string s2 = char.convertfromutf32(0x4e07); //万

    int n1 = char.converttoutf32("abc", 1);    //66
    int n2 = char.converttoutf32("万", 0);     //19975

    textbox1.text = string.concat(s1, "n", s2, "n", n1, "n", n2);
}

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getunicodecategory():
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protected void button1_click(object sender, eventargs e)
{
    char c;
    string str = "";
    for (int i = 20; i < 256; i++)
    {
        c = convert.tochar(i);
        str += string.format("{0}t{1}t{2}n", i, c, char.getunicodecategory(c));
    }
    textbox1.text = str;
}

本文来源：http://www.gdgbn.com/jiaocheng/28669/