获取Android手机中SIM卡状态

public String readSIMCard() {
TelephonyManager tm = (TelephonyManager)this.getSystemService(TELEPHONY_SERVICE);//取得相关系统服务
StringBuffer sb = new StringBuffer();
switch(tm.getSimState()){ //getSimState()取得sim的状态 有下面6中状态
case TelephonyManager.SIM_STATE_ABSENT :sb.append("无卡");break;
case TelephonyManager.SIM_STATE_UNKNOWN :sb.append("未知状态");break;
case TelephonyManager.SIM_STATE_NETWORK_LOCKED :sb.append("需要NetworkPIN解锁");break;
case TelephonyManager.SIM_STATE_PIN_REQUIRED :sb.append("需要PIN解锁");break;
case TelephonyManager.SIM_STATE_PUK_REQUIRED :sb.append("需要PUK解锁");break;
case TelephonyManager.SIM_STATE_READY :sb.append("良好");break;
}

if(tm.getSimSerialNumber()!=null){
sb.append("@" + tm.getSimSerialNumber().toString());
}else{
sb.append("@无法取得SIM卡号");
}

if(tm.getSimOperator().equals("")){
sb.append("@无法取得供货商代码");
}else{
sb.append("@" + tm.getSimOperator().toString());
}

if(tm.getSimOperatorName().equals("")){
sb.append("@无法取得供货商");
}else{
sb.append("@" + tm.getSimOperatorName().toString());
}

if(tm.getSimCountryIso().equals("")){
sb.append("@无法取得国籍");
}else{
sb.append("@" + tm.getSimCountryIso().toString());
}

if (tm.getNetworkOperator().equals("")) {
sb.append("@无法取得网络运营商");
} else {
sb.append("@" + tm.getNetworkOperator());
}
if (tm.getNetworkOperatorName().equals("")) {
sb.append("@无法取得网络运营商名称");
} else {
sb.append("@" + tm.getNetworkOperatorName());
}
if (tm.getNetworkType() == 0) {
sb.append("@无法取得网络类型");
} else {
sb.append("@" + tm.getNetworkType());
}
return sb.toString();
}