\n if (boolean expression #1) {
\n\/\/ \u5982\u679c\u5e03\u5c14\u8868\u8fbe\u5f0f #1 \u4e3a\u771f\u65f6\u6267\u884c\u7684\u4ee3\u7801
\n} else if (boolean expression #2) {
\n\/\/ <\/span><\/em>\u5982\u679c\u5e03\u5c14\u8868\u8fbe\u5f0f #2 \u4e3a\u771f\u65f6\u6267\u884c\u7684\u4ee3\u7801<\/span><\/em>
\n } else if (boolean expression #n) {
\n\/\/ <\/span><\/em>\u5982\u679c\u5e03\u5c14\u8868\u8fbe\u5f0f #n \u4e3a\u771f\u65f6\u6267\u884c\u7684\u4ee3\u7801<\/span><\/em>
\n } else {
\n\/\/ \u5982\u679c\u4ee5\u4e0a\u5e03\u5c14\u8868\u8fbe\u5f0f\u90fd\u4e3a\u5047\u65f6\u6267\u884c\u7684\u4ee3\u7801
\n} <\/span><\/em><\/p>\n
3. \u8bb0\u4f4f\u4e00\u70b9\u5c31ok\uff0c\u5f53\u4f60\u7684\u4e00\u5806\u6761\u4ef6\u5f0f\u4e2d\u7684\u67d0\u6761\u4e3a\u771f\uff0c\u5219\u6b64\u6761\u76f8\u5e94\u7684\u4ee3\u7801\u5c06\u88ab\u6267\u884c\uff0c\u5269\u4f59\u7684\u6761\u4ef6\u5f0f\u540c\u65f6\u88ab\u5ffd\u7565\u3002<\/p>\n
4. \u4e00\u4e2a\u6761\u4ef6\u5f0f\u4e2d\u53ea\u80fd\u542b\u6709\u4e00\u5bf9if\u548celse\uff0c\u4f46\u5374\u53ef\u4ee5\u5305\u542b\u65e0\u9650\u4e2aelse if\u3002<\/p>\n
5. \u4e00\u4e2a\u7b49\u53f7\uff1a\u8d4b\u503c\u7ed9\u4e00\u4e2a\u53d8\u91cf\uff1b\u4e24\u4e2a\u7b49\u53f7\uff1a\u67d0\u67d0\u548c\u67d0\u67d0\u76f8\u7b49\u3002<\/p>\n
6. constrain()\u51fd\u6570\u5e94\u7528 7. \u53d1\u73b0\u4e00\u70b9\uff0c\u5728\u505a\u4e00\u4e2a\u4f8b\u5b50\u7684\u65f6\u5019\uff1a\u65b9\u5757\u5411\u53f3\u6ed1\u52a8\uff0c\u5230X\u8f74\u7b49\u4e8e100\u7684\u65f6\u5019\u505c\u6b62\uff0c\u6211\u8fd9\u4e48\u5199\uff1a \u5f53\u7136\uff0c\u6700\u7b80\u5355\u7684\u65b9\u5f0f\u8fd8\u662fx= constrain(x,0,100);<\/span><\/em><\/p>\n 8. \u7c7b\u4f3c&&\u4ee5\u53ca||\u8fd9\u4e9b\u903b\u8f91\u8868\u8fbe\u5f0f\u53ef\u4ee5\u5199\u5728if\u7684\u540c\u4e00\u884c\uff0c\u4f8b\u5982if(mouseX < 100 && mouseY < 100)<\/p>\n 9. \u7ec3\u4e605_6\uff0c\u628a\u8fd0\u884c\u7a97\u53e3\u5206\u4e3a\u56db\u4e2a\u77e9\u5f62\uff0c\u9f20\u6807\u79bb\u5f00\u4e4b\u524d\u505c\u7559\u7684\u65b9\u5757\u540e\u989c\u8272\u7531\u767d\u6e10\u53d8\u5165\u9ed1\u3002\u4f4e\u667a\u5546\u7684\u6211\u6ca1\u6709\u65e5\u51fa\u6765\uff0c\u770b\u4e86\u7b54\u6848\u540e\u53d1\u89c9\u548c\u6211\u7684\u601d\u8def\u5b8c\u5168\u4e0d\u4e00\u6837\uff0c\u800c\u4e14\u6211\u603b\u89c9\u5f97\u6709\u5176\u5b83\u5b9e\u73b0\u65b9\u6cd5\uff08\u867d\u7136Daniel\u8001\u5934\u7684\u65b9\u6cd5\u4e5f\u5e76\u4e0d\u590d\u6742\u3002\u5b83\u7684\u5173\u952e\u70b9\uff1a\u8bbe\u7f6e\u6bcf\u4e2a\u65b9\u5757\u7684\u4eae\u5ea6\u4e00\u76f4\u5728\u9012\u51cf\uff0c\u6ce8\u610f\u662f\u4e00\u76f4\uff09\u3002\u6e90\u6587\u4ef6<\/a>.<\/p>\n 10. \u6309\u94ae\u7684\u7528\u6cd5\uff1a<\/p>\n boolean button = \u00a0false;<\/em><\/span><\/p>\n int x = 50;<\/em><\/span><\/p>\n int y \u00a0= 50;<\/em><\/span><\/p>\n int w \u00a0 = 100;<\/em><\/span><\/p>\n int h \u00a0= 75;<\/em><\/span><\/p>\n void setup()\u00a0 {<\/em><\/span><\/p>\n size(200,200);<\/em><\/span><\/p>\n }<\/em><\/span><\/p>\n void draw()\u00a0 {<\/em><\/span><\/p>\n if (mouseX >\u00a0 x && mouseX < x +\u00a0 w && mouseY >\u00a0 y && mouseY <\u00a0 y + h && mousePressed) {<\/em><\/span><\/p>\n button \u00a0 \u00a0 = \u00a0 \u00a0 \u00a0 true;<\/em><\/span><\/p>\n }\u00a0 else{<\/em><\/span><\/p>\n button \u00a0 \u00a0 = \u00a0 \u00a0 \u00a0 false;<\/em><\/span><\/p>\n }<\/em><\/span><\/p>\n if (button)<\/em><\/span><\/p>\n {<\/em><\/span><\/p>\n background(255);<\/em><\/span><\/p>\n stroke(0);<\/em><\/span><\/p>\n }\u00a0 else{<\/em><\/span><\/p>\n background(0);<\/em><\/span><\/p>\n stroke(255);<\/em><\/span><\/p>\n }<\/em><\/span><\/p>\n fill(175);<\/em><\/span><\/p>\n rect(x,y,w,h);<\/em><\/span><\/p>\n }<\/em><\/span><\/p>\n \n 11. \u70b9\u4e00\u4e0b\uff0c\u6362\u80cc\u666f\u8272\uff0c\u518d\u70b9\u4e00\u4e0b\uff0c\u6362\u56de\u6765\uff1a<\/p>\n boolean button = false;<\/span><\/em><\/p>\n int x = 50;<\/span><\/em><\/p>\n int y = 50;<\/span><\/em><\/p>\n int w = 100;<\/span><\/em><\/p>\n int h = 75;<\/span><\/em><\/p>\n void setup() {<\/span><\/em><\/p>\n size(200,200);<\/span><\/em><\/p>\n }<\/span><\/em><\/p>\n void draw() {<\/span><\/em><\/p>\n if (button) {<\/span><\/em><\/p>\n background(255);<\/span><\/em><\/p>\n stroke(0);<\/span><\/em><\/p>\n } else {<\/span><\/em><\/p>\n background(0);<\/span><\/em><\/p>\n stroke(255);<\/span><\/em><\/p>\n }<\/span><\/em><\/p>\n fill(175);<\/span><\/em><\/p>\n rect(x,y,w,h);<\/span><\/em><\/p>\n }<\/span><\/em><\/p>\n \/\/ When the mouse is pressed, the state of the button is toggled.<\/span><\/em><\/p>\n \/\/ Try moving this code to draw() like in the rollover example.\u00a0 What goes wrong?<\/span><\/em><\/p>\n void mousePressed() {<\/span><\/em><\/p>\n if (mouseX > x && mouseX < x+w && mouseY > y && mouseY < y+h) {<\/span><\/em><\/p>\n button = !button;<\/span><\/em><\/p>\n }<\/span><\/em><\/p>\n }<\/span><\/em><\/p>\n \n 12.\u00a0 \u4e00\u4e2a\u8bbe\u5b9a\u5e03\u5c14\u53d8\u91cf\u7684\u4f8b\u5b50\uff0c\u9f20\u6807\u70b9\u51fb\u540e\uff0c\u7403\u4ece\u5de6\u8fb9\u79fb\u52a8\u5230\u53f3\u8fb9\u3002\u5148\u8bbe\u5b9a\u5e03\u5c14\u53d8\u91cfgoing\u4e3a\u5047\uff0c\u518d\u8bbe\u5b9a\u9f20\u6807\u70b9\u51fb\u540e\uff08void mousePressed()\uff09going\u4e3a\u771f\uff0c\u7136\u540e\u8bbe\u5b9agoing\u4e3a\u771f\u65f6circleX=circleX+1;\u3002\u6e90\u6587\u4ef6<\/a><\/p>\n \n 13. \u8fd9\u91cc\u8bf4\u4e00\u4e0b\u5e03\u5c14\u53d8\u91cf\uff0c\u5e03\u5c14\u53d8\u91cf\u662f\u4e00\u4e2a\u53ea\u80fd\u4e3a\u771f\u6216\u5047\u7684\u53d8\u91cf\u3002\u7533\u660e\u65b9\u5f0f\u4e3aboolean+\u540d\u79f0=false\uff1b\uff08\u6216true\uff09<\/p>\n \n 14. \u5728\u4f8b5-6\u4e2d\uff0c\u4ed6\u63d0\u51fa\u4e86\u4e00\u4e2a\u8d1f\u7684\u901f\u5ea6\u7684\u6982\u5ff5\uff0c\u610f\u601d\u5c31\u662f\u4e0e\u6b63\u7684\u901f\u5ea6\u76f8\u53cd\u8fd0\u884c\uff08\u5176\u5b9e\u5c31\u662f\u5f53x\u5230\u8fbe\u591a\u5c11\u7684\u65f6\u5019\uff0c\u5f00\u59cb\u9012\u51cf\uff09\uff0c\u8fd9\u5c31\u51fa\u73b0\u4e86\u4e00\u4e2a\u4e0d\u505c\u5de6\u53f3\u79fb\u52a8\u7684\u7403\uff1a<\/p>\n int x = 0;<\/span><\/em><\/p>\n int speed = 1;<\/span><\/em><\/p>\n void setup() {<\/span><\/em><\/p>\n size(200,200);<\/span><\/em><\/p>\n smooth();<\/span><\/em><\/p>\n }<\/span><\/em><\/p>\n void draw() {<\/span><\/em><\/p>\n background(255);<\/span><\/em><\/p>\n \/\/ Add the current speed to the x location.<\/span><\/em><\/p>\n x = x + speed;<\/span><\/em><\/p>\n \/\/ Remember, || means “or.”<\/span><\/em><\/p>\n
\n if (r > 255) {
\nr = 255;
\n} else if (r < 0) { r = 0; } <\/span><\/em>
\n\u7b49\u540c\u4e8e
\n r = constrain(r,0,255); <\/span><\/em><\/p>\n
\n if (x>99) {<\/span><\/em>
\n x=99;
\n} else {
\nx=x+1;}
\n}<\/em><\/span>
\n<\/em> \u65b9\u5757\u505c\u662f\u505c\u4e0b\u6765\u4e86\uff0c\u4f46\u662f\u5374\u5728\u4e0d\u65ad\u5de6\u53f3\u98a4\u6296\uff0c\u540e\u6765\u6539\u6210\u8fd9\u6837\uff1a
\n if (x>99) {
\nx=100;
\n} else {
\nx=x+1;}
\n}<\/span><\/em>
\n\u6b63\u5e38\u3002<\/p>\n![\"Exercise](\"https:\/\/learn.travelchinawith.me\/wp-content\/uploads\/2009\/09\/pr3-1.gif\" "\\"Exercise")
<\/a>
\n<\/em><\/span><\/p>\n
\n<\/em><\/span><\/p>\n
\n<\/span><\/em><\/p>\n
\n<\/span><\/em><\/p>\n
\n<\/span><\/em><\/p>\n
\n<\/span><\/em><\/p>\n
\n<\/span><\/em><\/p>\n
\n<\/span><\/em><\/p>\n
\n<\/span><\/em><\/p>\n
\n<\/span><\/em><\/p>\n
\n<\/span><\/em><\/p>\n