下面提供給大家的是JAVA中全半角之間轉換的代碼，相信對剛學JAVA的朋友會有很大幫助。

 public class change {

public static void main(String[] args) {

String QJstr="全角轉半角ＤＡＯ";

String result=SBCchange(QJstr);

System.out.println(QJstr+"\n"+result);

}

public static final String SBCchange(String QJstr)
{
String outStr="";
String Tstr="";
byte[] b=null;

for(int i=0;i<QJstr.length();i++)
{
try
{
Tstr=QJstr.substring(i,i+1);
b=Tstr.getBytes("unicode");
}
catch(java.io.UnsupportedEncodingException e)
{
e.printStackTrace();
}

if (b[3]==-1)
{
b[2]=(byte)(b[2]+32);
b[3]=0;

try
{
outStr=outStr+new String(b,"unicode");
}
catch(java.io.UnsupportedEncodingException e)
{
e.printStackTrace();
}
}else outStr=outStr+Tstr;
}

return outStr;
}

}







public class Test {
public static void main(String[] args) {
String QJstr = "hello";
String QJstr1 = "ｈｅｈｅ";

String result = BQchange(QJstr);
String result1 = QBchange(QJstr1);

System.out.println(QJstr + "\n" + result);
System.out.println(QJstr1 + "\n" + result1);
}

// 半角轉全角
public static final String BQchange(String QJstr) {
String outStr = "";
String Tstr = "";
byte[] b = null;

for (int i = 0; i< QJstr.length(); i++) {
try {
Tstr = QJstr.substring(i, i + 1);
b = Tstr.getBytes("unicode");
} catch (java.io.UnsupportedEncodingException e) {
e.printStackTrace();
}
if (b[3] != -1) {
b[2] = (byte) (b[2] - 32);
b[3] = -1;
try {
outStr = outStr + new String(b, "unicode");
} catch (java.io.UnsupportedEncodingException e) {
e.printStackTrace();
}
} else
outStr = outStr + Tstr;
}
return outStr;
}

// 全角轉半角
public static final String QBchange(String QJstr) {
String outStr = "";
String Tstr = "";
byte[] b = null;

for (int i = 0; i< QJstr.length(); i++) {
try {
Tstr = QJstr.substring(i, i + 1);
b = Tstr.getBytes("unicode");
} catch (java.io.UnsupportedEncodingException e) {
e.printStackTrace();
}
if (b[3] == -1) {
b[2] = (byte) (b[2] + 32);
b[3] = 0;
try {
outStr = outStr + new String(b, "unicode");
} catch (java.io.UnsupportedEncodingException e) {
e.printStackTrace();
}
} else
outStr = outStr + Tstr;
}
return outStr;
}
}



/**/// /
// / 轉全角的函數(SBC case)
// /
// /任意字符串
// /全角字符串
// /
// /全角空格為12288，半角空格為32
// /其他字符半角(33-126)與全角(65281-65374)的對應關系是：均相差65248
// /
public static String ToSBC(String input) {
// 半角轉全角：
char[] c = input.toCharArray();
for (int i = 0; i< c.length; i++) {
if (c[i] == 32) {
c[i] = (char) 12288;
continue;
}
if (c[i]< 127)
c[i] = (char) (c[i] + 65248);
}
return new String(c);
}

/**/// /
// / 轉半角的函數(DBC case)
// /
// /任意字符串
// /半角字符串
// /
// /全角空格為12288，半角空格為32
// /其他字符半角(33-126)與全角(65281-65374)的對應關系是：均相差65248
// /
public static String ToDBC(String input) {
char[] c = input.toCharArray();
for (int i = 0; i< c.length; i++) {
if (c[i] == 12288) {
c[i] = (char) 32;
continue;
}
if (c[i]> 65280&& c[i]< 65375)
c[i] = (char) (c[i] - 65248);
}
return new String(c);